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ASP.NET Hosting - ASPHostPortal.com :: How To Create a Help Desk Web Application using ASP.NET

clock May 24, 2016 20:04 by author Armend

Suppose you work for a small to midsize company that employs 50-100 workers. The Help Desk -- a subsidiary of the Information Services Division -- is in charge of trouble tickets regarding general PC issues such as email, viruses, network issues, etc. Initially, the Help Desk team stored this information in Excel spreadsheets, but as the company has grown, managing these spreadsheets has become tedious and time consuming.

The Help Desk has asked you to devise a more efficient solution that could be developed internally, saving the company money. As you start to think about it, the following requirements are apparent: fields for the submitter's first and last name, as well as their email address. You'll also need combo boxes for indicating ticket severity (low, medium, high), department, status (new, open, resolved), employee working on the issue, as well as an area for comments. Of all the solutions available, creating an internal help desk Web application with ASP.NET is relatively simple.

In the following article, we'll see how to implement these features in an ASP.NET help desk Web application using a database-driven approach,
Creating the JavaScript File
Because creating the JavaScript file is the easiest of the work left, we'll do this next. From the Solution Explorer, follow these steps:

Creating the Help Desk Class

Now that we have our data coming in, we need to be able to record a help desk ticket submission. We need to create an event handler in a class to handle it. Let's first create a help desk class by doing the following:

  •     Right click the project solution.
  •     Choose Add>New Item.
  •     In the Add New Item window, select Class.cs.
  •     In the name text field, type "HelpDesk" and then click Add.

Double click HelpDesk.cs from the Solution Explorer, which will show the empty class as shown below:

using System;
using System.Collections.Generic;
using System.Linq;
using System.Web;
namespace HelpDesk
{
    public class HelpDesk
    {
    }
}

We need to import three libraries as shown below:

using System;
using System.Collections.Generic;
using System.Linq;
using System.Web;
using System.Data;
using System.Configuration;
using System.Data.SqlClient;
namespace HelpDesk
{
    public class HelpDesk
    {
    }
}

The first library (System.Data) allows us to work with stored procedures in ADO.NET, the second (System.Configuration) allows us to reference a connection key from configuration file and the last (System.Data.SqlClient) one allows us to connect to SQL Server.

 

 



ASP.NET 5 Hosting - ASPHostPortal :: SEO For ASP.NET Web Sites

clock December 16, 2015 00:36 by author Kenny

SEO For ASP.NET Web Sites

One of the main sources of audience for these internet applications are the Search Engines like Google, Bing, Yahoo etc. Hence, the end application should not only handle your business problems efficiently but also follow some simple rules so that it yields good results in internet arena. This article, will list some of the simple guidelines which you need to consider if your Asp.Net application is an internet site.

1.    Add descriptive and unique Page Title for every page

Every page in your website should have a unique and descriptive page title that can describe what the page offers. You can set the Page Title either declaratively or in the code behind file. Refer below,

In ASPX,

<%@ Page Language="C#" AutoEventWireup="true" Title="My Home Page"  CodeFile="Default.aspx.cs" Inherits="_Default" %>

In code behind,

Page.Title = "My Home Page";

2.    Links should be hyperlinks, no linkbutton or javascript navigation for crawlable links

Make sure all your links in your page are hyperlinks. Search engines can crawl a page only if it is linked through a hyper link (anchor tag). Javascript navigations are not search engine friendly since search engines will not understand it.

3.    Use javascript navigation for site related pages that have no search values

Page rank is distributed across the links on your page. Some of the internal website pages like About us, disclaimer, Registration, login, contact us, user profile pages can be navigated through javascript so that the page rank are not distributed to them. Doing like this will make rest of the crawlable content links benefited.

4.    Add Meta Keyword and Description tag for every page

Add Meta keyword and Meta description tag with relevant contents. Search engines will use these tags to understand what the page offers. You can dynamically set the meta tags from codebehind file using the below code,

HtmlHead head = (HtmlHead)Page.Header;

 HtmlMeta metasearch1 = new HtmlMeta();

 HtmlMeta metasearch2 = new HtmlMeta();  

 metasearch1.Name = "descriptions";

 metasearch1.Content = "my personal site";

 head.Controls.Add(metasearch1);

 metasearch2.Name = "keywords";

 metasearch2.Content = "ASP.Net,C#,SQL";

 head.Controls.Add(metasearch2);

The above code will add the below Meta tags to output html.

<meta name="descriptions" content="my personal site" />

<meta name="keywords" content="ASP.Net,C#,SQL" />

In ASP.Net 4.0, Microsoft added 2 new properties on the Page directive (Page object) that lets you to define the Meta keywords and Description declaratively and dynamically from codebehind.

In ASPX,

<%@ Page Language="C#" AutoEventWireup="true" MetaKeywords="asp.net,C#" MetaDescription="This is an asp.net site that hosts asp.net tutorials" CodeFile="Default.aspx.cs" Inherits="_Default" %>

In codebehind,

protected void Page_Load(object sender, EventArgs e)

    {

        Page.MetaKeywords = "asp.net,C#";

        Page.MetaDescription = "This is an asp.net site that hosts asp.net tutorials.";

    }

The similar can thing can be achieved in previous versions of .Net Framework by using a custom BasePage class.

5.    Make descriptive urls

Make your website URL descriptive. URL’s that has lots of query string values, numeric ids are not descriptive. It will provide enough information what the page offers. For example, http://www.example.com/products.aspx?catid=C91E9918-BEC3-4DAA-A54B-0EC7E874245E is not descriptive as http://www.example.com/Windows-Hosting

Apart from other parameters, search engines will also consider the website url to match your page for a searched keyword.



ASP.NET Hosting - ASPHostPortal.com :: Creating please wait message in the button on ASP.NET website

clock October 23, 2015 18:41 by author Dan

Sometimes we need please wait message button in our website to inform the visitor that their submission still in progress. Today, we will explain about creating please wait message in the button on ASP.NET website. You can copy below code to please wait message in the button.

<%@ Page Language="C#" AutoEventWireup="true" CodeFile="PleaseWaitButton.aspx.cs"
   Inherits="PleaseWaitButton" %>

<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN"
"http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">
<html xmlns="http://www.w3.org/1999/xhtml">
<head runat="server">
   <title>Untitled Page</title>
</head>
<body>
   <form id="form1" runat="server">
       <div>
           <div>
               <asp:Button ID="Button1" runat="server" Text="Button" />
           </div>
       </div>
   </form>
</body>
</html>

using System;
using System.Data;
using System.Configuration;
using System.Collections;
using System.Web;
using System.Web.Security;
using System.Web.UI;
using System.Web.UI.WebControls;
using System.Web.UI.WebControls.WebParts;
using System.Web.UI.HtmlControls;

public partial class PleaseWaitButton : System.Web.UI.Page
{
   protected void Button1_Click(object sender, System.EventArgs e)
   {
       System.Threading.Thread.Sleep(5000);
       ClientScript.RegisterClientScriptBlock(this.GetType(), "reset",
 "document.getElementById('" + Button1.ClientID + "').disabled=false;", true);
   }

   protected void Page_Load(object sender, System.EventArgs e)
   {
       System.Threading.Thread.Sleep(5000);
       Button1.Attributes.Add("onclick", ClientScript.GetPostBackEventReference(Button1, "") + ";
this.value='Please wait...';this.disabled = true;");
   }

}


Finish, happy coding.

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ASP.NET Hosting - ASPHostPortal.com :: How to Check Duplicate User Names In ASP.NET Web Pages Sites

clock October 5, 2015 11:39 by author Kenny

How to Check Duplicate User Names In ASP.NET Web Pages Sites

The Web Pages Starter Site template provides a useful starting point for developing a Razor Web Pages site that includes membership. But it doesn't include any mechanism for preventing duplicate user names. This article offers one solution to the problem that uses jQuery.

If you ask how to prevent duplicate user names in forums, one of the suggestions that is often put forward is to apply a unique constraint in the database column that holds the user name. Any attempt to submit a duplicate value will result in an exception being raised in the relevant database provider. You can catch this exception and show the user an appropriate message. This works but it's a fairly clunky solution. And many people feel that you should not use exceptions as a means to manage your business rules.

The solution featured in this article uses AJAX to query the database and to give the user immediate feedback when they enter their chosen user name. The AJAX call requests a page that exists purely to query the database to see if the selected user name is already in use. The solution also includes a server side chekc to ensure that users who have disabled JavaScript so not slip through the net. The solution requires a couple of amendments to the Register.cshtml file in the Starter Site, and the addition of 3 files. But first, the changes to the Register.cshtml page. The first change is in the inclusion of a JavaScript file called dupecheck.js.

@* Remove this section if you are using bundling *@
@section Scripts {
    <script src="~/Scripts/jquery.validate.min.js"></script>
    <script src="~/Scripts/jquery.validate.unobtrusive.min.js"></script>
    <script src="~/Scripts/dupecheck.js"></script>
}

And the second is the server side check to see if the username is in use:

if(Functions.IsDuplicate(email)){
    ModelState.AddError("email", "User name is already taken");
}

I placed this in the if(IsPost) section just after the initial variables that represent the submitted values (email, password and confirmPassword) are declared. The code calls a function named IsDuplicate. The function is declared in a file called Functions.cshtml which is placed in a folder called App_Code:

@functions {
    public static bool IsDuplicate(string username){
        var db = Database.Open("StarterSite");
        var commandText = @"SELECT COUNT(Email) FROM UserProfile WHERE Email = @0";
        return (int)db.QueryValue(commandText, username) > 0;
    }
}

Note that the name of the folder is important. The function returns a bool. The value of the bool is determined as a result if the SQL query which gets a count of the rows containing the provided user name. By default, the Starter Site uses a column called Email in the UserProfile table for the storage of user names. This function is also called in a separate file named DupeCheck.cshtml. This file is placed in the root of the site:

@{
    Layout = null;
    if(IsAjax){
        var username = Request["username"];
        var result = Functions.IsDuplicate(username);
        Json.Write(new { isDupe = result }, Response.Output);
    }
}

DupeCheck.cshtml is designed to work exclusively with AJAX. The code includes an instruction to nullify any layout pages that might have been set in a _PageStart file, and then it uses the IsAjax property to determine if the page has been requested via an AJAX call. If it has, it uses the IsDuplicate method to check the availability of the posted username and returns the result to the calling code. The result is an anonymous type that has one propery: isDupe, which is a boolean. The anonymous type is serialised to JSON by the Json helper.

The final part of the solution is the dupecheck.js file. This uses jQuery:

$(function () {
    $('#email').change(function () {
        $.post(
            '/DupeCheck',
            { username: $(this).val() },
            function (data) {
                var emailValidation = $('span[data-valmsg-for="email"]');
                if (data.isDupe) {
                    if (emailValidation.hasClass('field-validation-valid')) {
                        emailValidation.removeClass('field-validation-valid');
                        emailValidation.addClass('field-validation-error');
                        emailValidation.text('That name is already taken!');
                    }
                } else {
                    if (emailValidation.hasClass('field-validation-error')) {
                        emailValidation.removeClass('field-validation-error');
                        emailValidation.addClass('field-validation-valid');
                        emailValidation.text('');
                    }
                }
            },'json'
        );
    });
});

An event handler is attached to the change event of the user name input (which has an id if email in the Starter Site). The current value is posted to the DupeCheck.cshtml page via AJAX. The code above checks the response from the server to see if the value is a duplicate, and if it is, an appropriate error message is displayed to the user.

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ASP.NET Hosting - ASPHostPortal.com :: How to Display Please Wait Screen for heavy loading task

clock October 1, 2015 19:31 by author Dan

To display Please Wait Screen

Add Following line in .aspx file

In head Tag

<head runat="server">

    <title>Please Wait Screen</title>

    <script language = "javascript">

    function showPleaseWait()

    {

        document.getElementById('PleaseWait').style.display = 'block';

    }

    </script>

</head>



In Body Tag

<body>

    <form id="form1" runat="server">

        <div class="helptext" id="PleaseWait" style="display: none; text-align:right; color:White; vertical-align:top;">

            <table id="MyTable" bgcolor="red">

                <tr>

                    <td>

                        <b><font color="white">Please Wait...</font></b>

                    </td>

                </tr>

            </table>

        <div>

            <asp:Button ID="Button1" runat="server" Text="Button" OnClick="Button1_Click"  onmouseup="showPleaseWait()"/>
   

Note: here "Please Wait Screen" display logic is on mouse up event, so whenever heavy task started on button click event, "Please Wait..." Message will be displayed.

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ASP.NET Hosting - ASPHostPortal.com :: Easy to Design Pie Chart and Donut Chart in ASP.NET

clock September 28, 2015 12:40 by author Kenny

Easy to Design Pie Chart and Donut Chart in ASP.NET

D3.js stands for Data-Driven Document. It is a JavaScript library using which we can manipulate documents based on data. The data can be fetched using multiple ways like Web Services, WCF Services, REST APIs or the relatively new Microsoft ASP.NET Web API amongst many others. Using D3, you can bind the data to the Document Object Model (DOM) and present that data with rich visualizations. D3 internally makes use of CSS, HTML and SVG capabilities to make your data presentable. It is powerful, fast and supports large datasets and dynamic behaviors for interactions and powerful and smooth animations.

D3.js provides easy and declarative selections of DOM nodes using W3C Selector APIs. D3 Selector APIs provides number of methods to manipulate nodes. For example –

  • Setting attributes and applying rich styles
  • Registering Event Listeners
  • You can add, remove and sort DOM nodes
  • You can change the HTML or the text contents of HTML elements
  • You can also have a direct selection/access to the DOM as each selection is an array of nodes

Likewise, we have various features of D3.js selectors which we can use to present data to our DOM nodes.

A simple selector example is the following:

var bodySelection = d3.select('body').style('background-color', 'blue');

In the above example, we are selecting body and changing its background color to blue. Another example would be as follows:

var divSelection = d3.selectAll('div').style('background-color', 'yellow');

In the above example, we are selecting all divs and changing its background color to yellow. If you are familiar with jQuery, the syntax looks similar to jQuery selectors or HTML5 Selectors.

D3 allows us to bind the data to the DOM elements and their attributes using a Data method which takes an array. For example:

d3.selectAll("div")
  .data([200,300,400,100])
  .style("height", function (data) { return data + "px"; });

In the above example, we are selecting all the div’s on the page and based on the index, the first value of an array will be passed to first div, second value to second div and so on.

In D3, you can also make use of Enter and Exit selector methods to create new nodes for incoming data, and remove outing nodes that are no longer used.

You can also apply transitions to nodes using D3. For example –

var area = d3.select('body')
            .append('svg')
            .attr('width', 500)
            .attr('height', 500);
 
var circle = area.append('rect')
                 .attr('width', 100)
                 .attr('height', 100)
                 .attr('fill', 'red');
 
circle.transition()
      .duration(2000)
      .delay(2000)
      .attr('width', 400)
      .each('start', function () {
            d3.select(this).attr('fill', 'green');})
      .transition()
      .duration(2000)
      .attr('height', 400)
      .transition()
      .duration(2000)
      .attr('width', 50)
      .transition()
      .duration(2000)
      .attr('height', 50)
      .each('end', function () {
            d3.select(this).attr('fill', 'blue'); });

In the above example, we are drawing a Rectangle and applying the transition to the same. Likewise, we can make use of various features of D3.js to present our data using rich visualizations.

A Quick overview of ASP.NET Web API

REST(REpresentational State Transfer) has emerged as the prominent way to create web services. By using REST we can build loose coupled services with data available on the web over HTTP protocol.

ASP.NET Web API is a platform for building RESTful applications. ASP.NET Web API is a framework using which we can build HTTP Services which can be called from a broad range of clients, browsers and mobile devices. ASP.NET Web API is the defacto standard of creating web services and replaces WCF.

When we think about exposing data on the web, we usually talk about four common operations which we use on a daily basis in our apps – CREATE, RETRIVE, UPDATE, DELETE.

We call these operations as CRUD operations. REST provides 4 basic HTTP verbs which we can map to our CRUD operations as described here - POST – CREATE, GET – RETRIVE, PUT – UPDATE, DELETE – DELETE.

By using REST, if you can connect to the web, any application can consume your data. When the data is pulled or pushed by using REST, the data is always serialized into or de-serialized from JSON or XML.

Setting up the application and ASP.NET Web API

To start designing the Pie chart and Donut chart, use the following tools and technologies:

  • Microsoft Visual Studio 2013 (Express or Professional)
  • Microsoft SQL Server 2012 (Express or Developer)
  • jQuery
  • D3.js
  • ASP.NET WEB API

Let’s first design the table where we can add our data. To design the table, open SQL Server Management Studio and write the following script:

CREATE TABLE [dbo].[CityPopulationTable](
    [CityID] [int] IDENTITY PRIMARY KEY,
    [CityName] [nvarchar](30) NULL,
    [Population] [int] NULL
)

Create an ASP.NET Web application by choosing Web Forms template. Then add the Entity Framework, jQuery and D3.js libraries into our web application using NuGet.

Once you add these libraries, right click on the Models folder in our Web application under Solution Explorer, and click on Add New Item. Choose Data  > ADO.NET Entity Data Model.

Using Entity Data Model Wizard, connect to our database and choose CityPopulationTable.

It’s time to implement the ASP.NET Web API into our project. Right click the web application and add a new folder with the name Controllers.

After adding the Web API, open Global.asax file and import two namespaces as shown here:

using System.Web.Http;
using System.Web.Routing;

Also add the following code to the Application_Start method –

GlobalConfiguration.Configure(WebApiConfig.Register);

The above line registers the Web API route in our web application. Now under App_Start folder, you will find WebApiConfig.cs file. Open this file and write the following code:

public static void Register(HttpConfiguration config)
{
    config.MapHttpAttributeRoutes();
 
    config.Routes.MapHttpRoute(
        name: "DefaultApi",
        routeTemplate: "api/{controller}/{id}",
        defaults: new { id = RouteParameter.Optional }
    );
    var json = config.Formatters.JsonFormatter;
    json.SerializerSettings.PreserveReferencesHandling = Newtonsoft.Json.PreserveReferencesHandling.Objects;
    json.SerializerSettings.ContractResolver = new CamelCasePropertyNamesContractResolver();
    config.Formatters.Remove(config.Formatters.XmlFormatter);
}

In the above code, we are configuring Web API to make use of JSON formatter with camel casing, as most of the JavaScript developer will expect JSON output in Camel casing.

Now modify the Get method of our Web API controller as shown here:

public class PieChartController : ApiController
{
    NorthwindEntities dataContext = new NorthwindEntities();
    // GET api/piechart
    public IEnumerable<CityPopulationTable> Get()
    {
        return dataContext.CityPopulationTables.ToList();
    }
}

In the above code, we have created an object of our Entity Data model which will give access to the tables. Then we are returning an IEnumerable of our object CityPopulationTables.

Let us design our Pie chart and Donut chart using the Web API data shown in above:

Creating D3 Charts

Add a HTML page with the name ‘CityPolulationPieChart.html’. Once you add the page, we will reference the jQuery and D3.js file in the page:

<!DOCTYPE html>
<html lang="en">
<head>
    <title>Pie Chart Example</title>
    <script src="Scripts/jquery-1.10.2.js"></script>
    <script src="Scripts/d3.js"></script>
</head>

We will make use of jQuery AJAX function to fetch the data from our Web API and display it in a Pie and Donut chart. Let’s add a DOM ready function into our <body> tag. In this function, we will first declare two arrays. First array will hold the data for our chart and the second array will hold the colors which we will use for our chart:

$(function () {
            var chartData = [];
            var colors = [];
});

In the next step, we will fetch the data from our Web API using jQuery $.ajax function. Add this code after our array declaration:

$.ajax({
        type: "GET",
        url: "api/PieChart",
        contentType: "application/json; charset=utf-8",
        dataType: "json",
        success: function (result) {
            $.each(result, function (i,j) {
                chartData.push(j.population);
                var currentColor = '#' + Math.floor(Math.random() * j.population+5566656).toString(16);
                colors.push(currentColor);
            });
            console.log(chartData);}
        error: function (msg) {
            $("#result").text(msg);
        }
});

Note: Although I have used success and error here for devs using an older version of jQuery, these methods have been deprecated from jQuery 1.8. You should replace them with .done() and fail().

In the above code, we are using a GET request with the Web API URL and the type of data set to JSON. On successful completion of the request, we are running a loop using $.each() which will push the fetched data into our chartData array. We are also generating colors and adding them into our colors array.

Now it’s time to use the D3 selector. We will use D3 selector to select the body and will append the SVG element to the same by setting its height and width. Add this code after console.log function. The code is shown below –

var radius = 300;
var colorScale = d3.scale.ordinal().range(colors);
                    
var area = d3.select('body').append('svg')
             .attr('width', 1500)
             .attr('height', 1500);

Also note that we are using the scale function of D3 which allows us to set the ordinal scale with the range to set the scale’s output range. We have also added a variable called radius which is set to 300.

The next step is to group the elements and draw an arc into our SVG as shown in the following code:

var pieGroup = area.append('g').attr('transform', 'translate(300, 300)');
var arc = d3.svg.arc()
                .innerRadius(0)
                .outerRadius(radius);

In the above code, we are using radius variable as the outer radius and fixing the inner radius to 0. As the next step, use a pie layout available under D3. Then pass the chart data and append it to our group ‘g’. The code is shown below –

var pie = d3.layout.pie()
       .value(function (data) { return data; })
var arcs = pieGroup.selectAll('.arc')
       .data(pie(chartData))
       .enter()
       .append('g')
       .attr('class', 'arc');

Also observe, we are using D3 selector to select arc class added at the end, which will select all the elements which has a class arc. In the last step,  append the path and fill the color from our array. We will also display the population data as text to our pie chart. The code is shown below –

arcs.append('path')
    .attr('d', arc)
    .attr('fill', function (d) { return colorScale(d.data); });
 
arcs.append('text')
    .attr('transform', function (data) { return 'translate(' + arc.centroid(data) + ')'; })
    .attr('text-anchor', 'middle')
    .attr('font-size', '1em')
    .text(function (data) { return data.data; });

Donut Chart

Designing a Donut chart is very simple. Just change the inner radius to something higher than zero. I am making it 200. The code is as shown here:

var arc = d3.svg.arc()
        .innerRadius(200)
        .outerRadius(radius);

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ASPHostPortal.com provides its customers with Plesk Panel, one of the most popular and stable control panels for Windows hosting, as free. You could also see the latest .NET framework, a crazy amount of functionality as well as Large disk space, bandwidth, MSSQL databases and more. All those give people the convenience to build up a powerful site in Windows server. ASPHostPortal.com offers ASP.NET hosting starts from $1/month only. They also guarantees 30 days money back and guarantee 99.9% uptime. If you need a reliable affordable ASP.NET Hosting, ASPHostPortal.com should be your best choice.



ASP.NET Hosting - ASPHostPortal.com :: Create DropDown and MultiselectDropDown Controls for ASP.NET

clock September 7, 2015 06:32 by author Dan

Description

This article discusses about two user controls written in ASP.NET. Working on a project recently, I needed to develop a custom DropDown control with multiselect options in the form of CheckBox. I searched around for something simple, yet useful for my needs, and I wasn't able to find anything, so I developed my own control. Later, I reused the code to create a regular DropDown control (no multiselect checkbox options). The two controls can be merged into one, but I might do that at a later stage. On to the controls.

DropDown

This control can be bound to a IListSource to fetch data to be populated, in addition to the regular Items collection that can be populated from the asp. Here are a few examples of how this control can be used in ASPX.

<%@ Register Src="Controls/DropDown.ascx" TagName="DropDown" TagPrefix="thp" %>

<thp:DropDown ID="DropDown1" runat="server" Width="200">
     <Items>
          <asp:ListItem Text="Some text" Value="0" Selected="True" />
          <asp:ListItem Text="Another option" Value="1" />
     </Items>
</thp:DropDown>

<thp:DropDown ID="DropDown2" runat="server" Width="200" DataSourceID="DataSource1"
            DataTextField="Name" DataValueField="Id" />

<thp:DropDown ID="DropDown3" runat="server" Width="200"
 OnNeedDataSource="DropDown3_NeedDataSource"
         DataTextField="Name" DataValueField="Id" OnClientChange="onDropDownChange" />

Here's a screenshot of what the above code would render:

Both controls support the following data events:

  • ItemDataBound - Fired after the object has been bound to an Item. The argument passes both the bound object (DataObject) and theListItem.
  • NeedDataSource - Fired when there's no DataSourceID specified. This event is helpful when you want to manually populate the controls with your data. See the source code provided for specifics on this, you can use either Items collection or create custom list source (or both).

MultiselectDropDown

The code and usage is exactly as the DropDown control. Here's a screenshot of all of the above scenarios:

The styling in the attached project uses .skin files in the default theme. You can easily modify these to fit your needs. Everything can be styled.

I hope you find this code useful. I recommend this to anyone that wants to start developing custom controls as it has very important features implemented, such as the IPostBackDataHandler interface to pass data between postbacks in a custom manner. It also features some niceDataBinding examples and how you can use and modify these to perform specific tasks.

Best ASP.NET 4.6 Hosting Recommendation

ASPHostPortal.com provides its customers with Plesk Panel, one of the most popular and stable control panels for Windows hosting, as free. You could also see the latest .NET framework, a crazy amount of functionality as well as Large disk space, bandwidth, MSSQL databases and more. All those give people the convenience to build up a powerful site in Windows server. ASPHostPortal.com offers ASP.NET MVC hosting starts from $1/month only. They also guarantees 30 days money back and guarantee 99.9% uptime. If you need a reliable affordable ASP.NET Hosting, ASPHostPortal.com should be your best choice.



ASP.NET MVC 6 Hosting - ASPHostPortal :: Remote Validation in ASP.NET MVC

clock August 24, 2015 08:07 by author Kenny

Remote Validation in ASP.NET MVC

ASP.NET is an open-source server-side Web application framework designed for Web development to produce dynamic Web pages. It was developed by Microsoft to allow programmers to build dynamic web sites, web applications and web services. ASP.NET MVC gives you a powerful, patterns-based way to build dynamic websites that enables a clean separation of concerns and that gives you full control over markup. Remote validation is used to make server calls to validate data without posting the entire form to the server when server side validation is preferable to client side.  It's all done set up model and controller which is pretty neat. 

Using the Code

To implement remote validation in an application we have two scenarios, one is without an additional parameter and the other is with an additional parameter. First we create an example without an additional parameter. In this example we check whether a username exists or not. If the username exists then that means the input user name is not valid. We create a view model class "UserViewModel" under the Models folder and that code is:

using System.Web.Mvc;  
namespace RemoteValidation.Models   
{  
    public class UserViewModel   
    {  
        public string UserName   
        {  
            get;  
            set;  
        }  
        public string Email   
        {  
            get;  
            set;  
        }  
    }  
}

 

Now we create a static data source, in other words we create a static list of UserViewModel in which we could check whether a username exists or not. You can also use the database rather than a static list. The following code snippet is for StaticData.

using RemoteValidation.Models;  
using System.Collections.Generic;  
 
namespace RemoteValidation.Code   
{  
    public static class StaticData   
    {  
        public static List < UserViewModel > UserList   
        {  
            get {  
                return new List < UserViewModel >   
                {  
                    new UserViewModel   
                    {  
                        UserName = "User1", Email = "[email protected]"  
                    },  
                    new UserViewModel   
                    {  
                        UserName = "User2", Email = "[email protected]"  
                    }  
                }  
            }  
        }  
    }  

 

Now we create a controller "ValidationController" in which we create an action method to check whether a user name exists or not and return a result as a JSON format. If the username exists then it returns false so that the validation is implemented on the input field. The following code snippet shows ValidationController under the Controllers folder.

using RemoteValidation.Code;  
using System.Linq;  
using System.Web.Mvc;  
 
namespace RemoteValidation.Controllers   
{  
    public class ValidationController: Controller   
    {  
        [HttpGet]  
        public JsonResult IsUserNameExist(string userName)   
        {  
            bool isExist = StaticData.UserList.Where(u = > u.UserName.ToLowerInvariant().Equals(userName.ToLower())).FirstOrDefault() != null;  
            return Json(!isExist, JsonRequestBehavior.AllowGet);  
        }  
    }  
}

 

Now we add remote validation on the UserName of the UserViewModel property as in the following code snippet.

using System.Web.Mvc;  
 
namespace RemoteValidation.Models   
{  
    public class UserViewModel   
    {  
        [Remote("IsUserNameExist", "Validation", ErrorMessage = "User name already exist")]  
        public string UserName   
        {  
            get;  
            set;  
        }  
        public string Email   
        {  
            get;  
            set;  
        }  
    }  

 

As in the preceding code snippet, the IsUserNameExist is a method of ValidationController that is called on the blur of an input field using a GET request. Now we create UserController under the Controllers folder to render a view on the UI.

using RemoteValidation.Models;  
using System.Web.Mvc;  
 
namespace RemoteValidation.Controllers   
{  
    public class UserController: Controller   
    {  
        [HttpGet]  
        public ActionResult AddUser()   
        {  
            UserViewModel model = new UserViewModel();  
            return View(model);  
        }  
    }  

Now we add jquery.validate.js and jquery.validate.unobtrusive.js to the project and create a bundle as in the following code snippet.

using System.Web.Optimization;  
 
namespace RemoteValidation.App_Start   
{  
    public class BundleConfig   
    {  
        public static void RegisterBundles(BundleCollection bundles)   
        {  
            bundles.Add(new StyleBundle("~/Content/css").Include(  
                "~/Content/css/bootstrap.css",  
                "~/Content/css/font-awesome.css",  
                "~/Content/css/site.css"));  
 
            bundles.Add(new ScriptBundle("~/bundles/jquery").Include(  
                "~/Scripts/jquery-{version}.js"));  
 
            bundles.Add(new ScriptBundle("~/bundles/jqueryval").Include(  
                "~/Scripts/jquery.validate*"));  
        }  
    }  

Thereafter we add the following keys in the web.config file.

<add key="ClientValidationEnabled" value="true" />   
<add key="UnobtrusiveJavaScriptEnabled" value="true" />  
 
 

Thereafter we create a view for the AddUser action method. The following code snippet is for the AddUser view.

@model RemoteValidation.Models.UserViewModel  
 
< div class = "panel panel-primary" > < div class = "panel-heading panel-head" > Add User < /div>    
    <div class="panel-body">    
        @using (Html.BeginForm())    
        {    
            <div class="form-horizontal">    
                <div class="form-group">    
                    @Html.LabelFor(model => model.UserName, new { @class = "col-lg-2 control-label" })    
                    <div class="col-lg-9">    
                        @Html.TextBoxFor(model => model.UserName, new { @class = "form-control" })    
                        @Html.ValidationMessageFor(model => model.UserName)    
                    </div > < /div>    
                <div class="form-group">    
                    @Html.LabelFor(model => model.Email, new { @class = "col-lg-2 control-label" })    
                    <div class="col-lg-9">    
                        @Html.TextBoxFor(model => model.Email, new { @class = "form-control" })    
                        @Html.ValidationMessageFor(model => model.Email)    
                    </div > < /div>                    
                <div class="form-group">    
                    <div class="col-lg-9"></div > < div class = "col-lg-3" > < button class = "btn btn-success"  
                     id = "btnSubmit"  
                     type = "submit" > Submit < /button>    
                    </div >
               < /div>    
            </div >  
} < /div>    
</div >   
@section scripts   
{  
    @Scripts.Render("~/bundles/jqueryval")  

Let's run the application and put values into the user name field to execute the remote validation as in the following image.

Figure 1: Remote validation on user name


Now we move to another option, we pass an additional parameter in the remote validation. We pass both the user name and email as a parameter and check whether the username and email combination exist or not on the email input. That's why we add one more method in ValidationController as in the following code snippet for it.

[HttpGet]  
public JsonResult IsUserExist(string email, string userName)   
{  
    bool isExist = StaticData.UserList.Where(u = > u.UserName.ToLowerInvariant().Equals(userName.ToLower()) && u.Email.ToLowerInvariant().Equals(email.ToLower())).FirstOrDefault() != null;  
    return Json(!isExist, JsonRequestBehavior.AllowGet);  

Now we call this method on the Email property of UserViewModel as in the following code snippet.

using System.Web.Mvc;  
 
namespace RemoteValidation.Models   
{  
    public class UserViewModel   
    {  
        [Remote("IsUserNameExist", "Validation", ErrorMessage = "User name already exist")]  
        public string UserName   
        {  
            get;  
            set;  
        }  
        [Remote("IsUserExist", "Validation", ErrorMessage = "User already exist", AdditionalFields = "UserName")]  
        public string Email   
        {  
            get;  
            set;  
        }  
    }  
}

As in the preceding code snippet, we are passing an additional field using AdditionalFields in Remote. If we must pass more than one parameter then these will be comma-separated. Now run the application and the result will be as shown in the following image.  



ASP.NET Hosting - ASPHostPortal.com :: How to Solve HTTP Error 500.19 and 500.21 in ASP.NET 4.0

clock June 18, 2015 08:48 by author Dan

I was attempting to set up a new ASP.NET 4.0 web on my dev machine, running Windows 7 and IIS 7. I ran into several errors, that I suspect others may encounter, and I had to search all over the web to find all the answers. So I’ve written this post in the hopes it saves some other dev the same headache I had!

So, first I created the new website and app pool identity, but when I hit the site for the first time, I got the following error:

HTTP Error 500.19 – Internal Server Error

The requested page cannot be accessed because the related configuration data for the page is invalid.
After searching for solutions, I found most had to do with permissions to the web.config file or actual locking of sections of the web.config file. I confirmed that the app pool identity had permissions to the file, and there were no locking attributes in the file. So something else had to be the issue. Then I found some post on asp.net forum.
It turns out that ASP.NET had not been configured fully on my machine. So, according to one of the answers on the post, the solution is to do the following steps:
1. Open control panel
2. Click on “Programs and Features”
3. Click on ”Turn windows features on/off”
4. Locate ”Internet Information services IIS” in the pop up window and expand its node
5. Expand the ”World Wide Web Service” node
6. Expand “Application Development Features” node
7. Check the check box of”ASP.NET”
8. Then click ok button
9. You will need to restart your computer (go get a cup of coffee…)

After restarting, and hitting the site again, I got this new error:

HTTP Error 500.21 – Internal Server Error

Handler “PageHandlerFactory-Integrated” has a bad module “ManagedPipelineHandler” in its module list
Another web search revealed that even though the step above enabled ASP.NET, it was not fully installed. To fix this problem basically, just open a command window and enter the command shown below (command is slightly different for 32-bit vs. 64-bit).
64-bit:
%windir%\Microsoft.NET\Framework64\v4.0.30319\aspnet_regiis.exe -i

32 bit:
%windir%\Microsoft.NET\Framework\v4.0.21006\aspnet_regiis.exe -i

If you get a permissions error, you need to run the window as an administrator. To do this, go to start |run, and type ‘cmd’, but hit Ctrl-Shift-Enter, instead of just Enter.
After doing that, I hit the site again, and it worked! Hope this has helped!

Best ASP.NET Hosting Recommendation

ASPHostPortal.com provides its customers with Plesk Panel, one of the most popular and stable control panels for Windows hosting, as free. You could also see the latest .NET framework, a crazy amount of functionality as well as Large disk space, bandwidth, MSSQL databases and more. All those give people the convenience to build up a powerful site in Windows server. ASPHostPortal.com offers ASP.NET MVC hosting starts from $1/month only. They also guarantees 30 days money back and guarantee 99.9% uptime. If you need a reliable affordable ASP.NET Hosting, ASPHostPortal.com should be your best choice.



ASP.NET Hosting - ASPHostPortal.com :: Sending an email using exchange server from the ASP.NET Application

clock February 2, 2015 07:27 by author Dan

The .NET Framework 1.x had a System.web.mail class to send an email from the ASP.NET system. While this namespace and these classes still exist in the .NET Framework form 2.0 and later, they have been expostulated and supplanted by the new Mail API in the System.net.mail namespace in the Asp.net 2.0 structure. Asp.net 1.x's System.web.mail API was focused around CDO libraries. With the new Apis, Microsoft moved far from CDONTS based wrapper Apis and composed the new API utilizing Com+ segments to enhance the execution.

ASP.NET 2.0 sends an email utilizing Smtpclient class. In the most fundamental arrangement, You need to set the hostname of the hand-off server in the event that you are utilizing trade server or localhost in the event that you are utilizing neighborhood SMTP administration, port (25 as a matter of course), authentican certifications, or pointed out pickup index through the Deliverymethod property.

Here is the template for the System.NET.Mail configuration.

<configuration>
<!– Add the email settings to the element –>
<system.net>
<mailSettings>
<smtp deliveryMethod=”PickupDirectory” from=”fromemailaddress”>
<network
host=”relayServerHost”
port=”portNumber”
userName=”username”
password=”password”
defaultCredentials=”true/false”/>
</smtp>
</mailSettings>
</system.net>
</configuration>

localhost – local web server SMTP administration – If you need to send an email through neighborhood SMTP Service of the web server, basically include emulating lines of code in your web.config to send an email from the ASP.NET Pages.

<system.net>
<mailSettings>
<smtp deliveryMethod=”PickupDirectoryFromIis”>
<network host=”(localhost)” port=”25″ defaultCredentials=”true” />
</smtp>
</mailSettings>
</system.net>

Exchange Server – If you need to send an email from existing trade server email account, you need to setup the transfer administration from your webserver to trade server. Emulating web.config setup permits you utilize hand-off administration for trade server.

How about we say's exchange server name is "exmail.domainname.com", exchange username and secret key is "exchangeuserid" and "exchangepassword", you web.config settings would be

<system.net>
<mailSettings>
<smtp>
<network host=”exmail.domainname.com” port=”25″ userName=”exchangeuserid” password=”exchangepassword” defaultCredentials=”false” />
</smtp>
</mailSettings>
</system.net>

Next step would be to make a class to send a messages utilizing SMTP Service: Note that emulating code utilizes Web.config settings. Remarked out code won't utilize web.config mail settings. In spite of the fact that its preferrable, on the off chance that you don't need email designs in web.config document, utilize the remarked out code to design and send an email from the ASP.NET pages.

using System;using System.Net;using System.Net.Mail;
public class SMTPEmailSender
{
public SMTPEmailSender()
{
//
// TODO: Add constructor logic here
//
}

public static void SendSMTPEmail(string senderMailAddress,
string recipientMailAddress,
string mailSubject,
string mailBody)
{

//Create MailMessage to send an email.
MailMessage message = new MailMessage(senderMailAddress, recipientMailAddress);
message.Subject = mailSubject;
message.Body = mailBody;

//Use SMTPClient to send an email.
//Uses SMTP settings from web.config
SmtpClient client = new SmtpClient();
client.Send(message);

//Uses SMTP Settings from Code
/*
//Sample Code
//SmtpClient smtp = new SmtpClient(“exmail.domainname.com”, portnumber);
//smtp.Credentials = new NetworkCredential(“exchangeuserid”, “exchangepassword”, “DOMAIN”);
//smtp.DeliveryMethod = SmtpDeliveryMethod.Network; //smtp.Send(message);
*/
}
}

Create a Test Page to send out emails. Here is the source code from the code behind to send an email from the test email page.

public partial class TestEmail : System.Web.UI.Page
{
protected void Page_Load(object sender, EventArgs e)
{
string fromEmailAddress = “[email protected]“;
string recipientEmailAddress = “[email protected]“;
string mailSubject = “Nik’s Website: Test Email”;
string mailBody = “Test Email.”;
if (recipientEmailAddress != null && recipientEmailAddress.Trim().Length != 0)
{
SMTPEmailManager.SendSMTPEmail(fromEmailAddress, recipientEmailAddress, mailSubject, mailBody);
}
Response.Write(“Test Email Sent Out”);
}
}

Best ASP.NET Hosting Recommendation

ASPHostPortal.com provides its customers with Plesk Panel, one of the most popular and stable control panels for Windows hosting, as free. You could also see the latest .NET framework, a crazy amount of functionality as well as Large disk space, bandwidth, MSSQL databases and more. All those give people the convenience to build up a powerful site in Windows server. ASPHostPortal.com offers ASP.NET hosting starts from $1/month only. They also guarantees 30 days money back and guarantee 99.9% uptime. If you need a reliable affordable ASP.NET Hosting, ASPHostPortal.com should be your best choice.



Cheap ASP.NET 4.5 Hosting

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