jQuery call page codebehind method

In asp.net application sometimes we need to call codebehind method from client script. In this post we will see how to call codebehind page method using jquery ajax.

To call codebehind page method from jquery we need to make method static. Also we need to add [WebMethod] attribute for method. So the code behind method will look like:

 [WebMethod]
  public static string GetMessage()
  {
   return "Codebehind method call...";
  }

We also need to add namespace using System.Web.Services; to add [WebMethod] attribute to code behind method.
Now we can call this codebehind method using jquery ajax like

var loc = window.location.href;
$.ajax({
         type: 'POST',
          url: loc + "/GetMessage",
          data: "{}",
          contentType: "application/json; charset=utf-8"
        
        })
        .success(function (response) {
          alert(response.d);

        })
        .error(function (response) {
          alert(response.d);
        });

Here using window.location.href we are getting url of aspx page and by appending method name to it we can call code behind method.

Below code demonstrats how to call codebehind method using jquery ajax and json

jQuery ajax call codebehind page method

<html xmlns="http://www.w3.org/1999/xhtml">
<head runat="server">
<title></title>
<script type="text/javascript" src="https://ajax.googleapis.com/ajax/libs/jquery/1.7.1/jquery.min.js"></script>
<script type="text/javascript">

$(document).ready(function () {
var loc = window.location.href;
$("#btnClick").click(function (event) {
$.ajax({
type: 'POST',
url: loc + "/GetMessage",
data: "{}",
contentType: "application/json; charset=utf-8"
})
.success(function (response) {
alert(response.d);
})
.error(function (response) {
alert(response.d);
});
});
});
</script>
</head>
<body>
<form id="form1" runat="server">
<div>
<asp:Button ID="btnClick" runat="server" Text="Button" />
</div>
</form>
</body>
</html>

Below is the code behind method that will get called by jquery ajax call:

using System;
using System.Web.Services;

namespace aspnetcontrol
{
  public partial class jquerycallpagemethod : System.Web.UI.Page
  {
    protected void Page_Load(object sender, EventArgs e)
    {

    }

    [WebMethod]
    public static string GetMessage()
    {
      return "Codebehind method call...";
    }
  }
}

Remove Hide blogger|blogspot header navbar

Blogger or Blogspot is the easy way to write blogs. In blogger by default it shows header navbar on top. To hide blogspot|blogger navbar from header follow the below steps:
1. Login to blogger account.
2. Go to Template in new blogger view
3. Then click on Edit Html.

hide remove blogspot header navbar using css

4. Search for <b:skin>
5. Below that add css:
#navbar-iframe
{
height:0px;
visibility:hidden;
display:none;
}
This will hide or disable the blogger default header navbar.

jQuery ajax handle exception thrown by wcf

When we work with jQuery Ajax call to WCF, it may possible that WCF service will thow an exception. And we need to catch that exception in jquery ajax error routine. In order to show or get exception thrown by service we need to configure includeExceptionDetailInFaults="True" for in behavior like:

<serviceBehaviors>
  <behavior name="">
    <serviceMetadata httpGetEnabled="true" />
    <serviceDebug includeExceptionDetailInFaults="true" />
  </behavior>
</serviceBehaviors>

Now when jquery ajax call revices error then exception comes in resposeText as Message.But we need extract Message from responseText as responseText comes as cominations of error details. This can be done using jQuery.parseJSON like:



 .error(function (response, q, t) {
          var r = jQuery.parseJSON(response.responseText);
        });

Now to get Message part we can use r.Message. This will give you the message that is sent by exception in wcf service.


 .error(function (response, q, t) {
          var r = jQuery.parseJSON(response.responseText);
          alert("Message: " + r.Message);
        });

Code for jQuery ajax handle exception thrown by wcf

<html xmlns="http://www.w3.org/1999/xhtml">
<head runat="server">
   <script type="text/javascript" src="https://ajax.googleapis.com/ajax/libs/jquery/1.7.1/jquery.min.js"></script>
  <title>Jquery ajax json call to wcf service</title>
  <script type="text/javascript">
    $(document).ready(function () {
      $("#btnClick").click(function () {
        var dto = { message: $("#messageinput").val() };
        $.ajax({
          type: 'GET',
          url: '<%= ResolveUrl("~/Service1.svc/get-json/GetMessage") %>',
          data: dto,
          contentType: "application/json; charset=utf-8"
        })
        .success(function (response) {
          alert(response.d);
        })
        .error(function (response, q, t) {
          var r = jQuery.parseJSON(response.responseText);
          alert("Message: " + r.Message);
          alert("StackTrace: " + r.StackTrace);
          alert("ExceptionType: " + r.ExceptionType);
          alert("ERROR" + response.d);
        });
      });
    });
  </script>
</head>
<body>
  <form id="form1" runat="server">
  <div>
    <input type="text" id="messageinput" />
    <asp:Button ID="btnClick" runat="server" Text="Button" />
  </div>
  </form>
</body>
</html>

Note: To test example of catch exception in jquery ajax thrown by wcf service, just throw an application exception or Exception with some message like:

    [WebGet()]
    [OperationContract]
    public string GetMessage(string message)
    {
      //return "WCF" + message;
      throw  new  ApplicationException("This is exception");
    }

Configure wcf service to call in jquery ajax json

In previous post we saw how to create wcf service to be get called by jquery ajax and json. After creating wcf service we need to configure wcf service in web.config in order to make it accessible.

wcf service configuration for jquery ajax call

Configure wcf service

  <system.serviceModel>
    <behaviors>
      <endpointBehaviors>
        <behavior name="GetJson">
          <enableWebScript />
        </behavior>
        <behavior name="PostJson">
          <webHttp />
        </behavior>
      </endpointBehaviors>
      <serviceBehaviors>
        <behavior name="">
          <serviceMetadata httpGetEnabled="true" />
          <serviceDebug includeExceptionDetailInFaults="false" />
        </behavior>
      </serviceBehaviors>
    </behaviors>
    <serviceHostingEnvironment aspNetCompatibilityEnabled="true" multipleSiteBindingsEnabled="true" />
    <services>
      <service name="aspnetcontrol.Service1">
        <endpoint address="get-json"
                  binding="webHttpBinding"
                  behaviorConfiguration="GetJson"
                  contract="aspnetcontrol.Service1" />
    
        <endpoint address="post-json"
                  binding="webHttpBinding"
                  behaviorConfiguration="PostJson"
                  contract="aspnetcontrol.Service1" />
      </service>
    </services>
  </system.serviceModel>

Create wcf service to call by jquery ajax json

In this post we will see how to create wcf service in C# that we can call through jquery ajax and json. The namespaces we need in wcf service are System.ServiceModel, System.ServiceModel.Web and System.ServiceModel.Activation.

create wcf service to be called by jquery ajax json

Example- WCF service to call by jquery ajax json

using System.ServiceModel;
using System.ServiceModel.Web;
using System.ServiceModel.Activation;
using System.Web;

namespace aspnetcontrol
{
  [ServiceContract(Namespace = "")]
  [AspNetCompatibilityRequirements(RequirementsMode = AspNetCompatibilityRequirementsMode.Allowed)]
  public class Service1 
  {
    [WebGet()]
    [OperationContract]
    public string GetMessage(string message)
    {
      return "WCF" + message;
    }
  }
}

Note: In above code important attributes are [ServiceContract(Namespace = "")], [OperationContract] and [WebGet()]. ServiceContract specifies that class defines service contract in application.
OperationContract specifies that a method defines and operation that is part of web service contract.
WebGet indicates service operation is logically a retrieval operation. In this way we can create wcf service to be called using jquery ajax json. In order to make service accessible we need to configure wcf service in web.config.

jQuery Ajax call to WCF service

In jQuery we can perform an asynchronous HTTP (Ajax) request. In this post we will see simple example of how jquery Ajax call to WCF service works. We can call wcf service using jquery ajax and json.

use jquery ajax to call wcf service
We can use $.ajax to call the wcf service like:
 var dto = { message: $("#messageinput").val() };
        $.ajax({
          type: 'GET',
          url: '',
          data: dto,
          contentType: "application/json; charset=utf-8"
        })
        .success(function (response) {
          alert(response.d);
        })
        .error(function (response) {
          alert("ERROR"+response.d);
        });


Here in above code snippet we have set various parameters for jquery ajax call like: type: 'GET' - means request is of type GET and not POST
url: '', here we have mentioned the url of wcf service, where Service1.svc is wcf service name, get-json is address set in the web.config wcf service and GetMessage is actual method in wcf service.
data: dto is the parameter data that we need to pass to wcf service method.

Example jquery ajax call to wcf service

<html xmlns="http://www.w3.org/1999/xhtml">
<head runat="server">
   <script type="text/javascript" src="https://ajax.googleapis.com/ajax/libs/jquery/1.7.1/jquery.min.js"></script>
  <title>Jquery ajax json call to wcf service</title>
  <script type="text/javascript">
   $(document).ready(function () {
      $("#btnClick").click(function () {
        var dto = { message: $("#messageinput").val() };
        $.ajax({
          type: 'GET',
          url: '<%= ResolveUrl("~/Service1.svc/get-json/GetMessage") %>',
          data: dto,
          contentType: "application/json; charset=utf-8"
        })
        .success(function (response) {
          alert(response.d);
        })
        .error(function (response) {
          alert("ERROR"+response.d);
        });
      });
    });
  </script>
</head>
<body>
  <form id="form1" runat="server">
  <div>
    <input type="text" id="messageinput" />
    <asp:Button ID="btnClick" runat="server" Text="Button" />
  </div>
  </form>
</body>
</html>

In above example we can type some message in textbox and pass message to wcf service using jquery ajax call and get it in respose back.

Note: To run above example we need to create wcf service and configure wcf service endpoint in web.config file properly

jquery set dropdownlist exact text

We have seen how to set selected option in dropdown list by text here set dropdownlist selected option by text. In that example we used :contains selector that will look for the text and the set text in dropdownlist as selected.

dropdownlist set exact selected text
But if dropdownlist have items with same texts instance then :contains selector will get all the items with matched text. This might show last matched item selected in dropdownlist. In this case we need to use alternate way to get exact text in dropdownlist and then set it selected.

Example to set selected option in dropdown by exact text [jquery]


<html xmlns="http://www.w3.org/1999/xhtml">
<head id="Head1" runat="server">
  <script type="text/javascript" src="https://ajax.googleapis.com/ajax/libs/jquery/1.7.1/jquery.min.js"></script>
  <title>set dropdown value</title>
  <script type="text/javascript">
    $(document).ready(function () {
      $("#go").click(function () {
        var inputText = $("#inputText").val();
        $("#numbers").each(function () {
          $('option', this).each(function () {
            if ($.trim($(this).text().toLowerCase()) == $.trim(inputText.toLowerCase())) {
              $(this).attr('selected', 'selected');
            };
          });
         });
       });
    });
 </script>
</head>
<body>
  <form id="form1" runat="server">
  <div>
    <label>Enter value from dropdown</label>
    <input type="text" id="inputText" />
    <asp:DropDownList ID="numbers" runat="server">
      <asp:ListItem Text="This is one" Value="1"></asp:ListItem>
      <asp:ListItem Text="This is one?" Value="2"></asp:ListItem>
      <asp:ListItem Text="This is three" Value="3"></asp:ListItem>
    </asp:DropDownList>
  </div>
  <input type="button" id="go" value="Go" />
  </form>
</body>
</html>

Summary: So by using :contains it might not work for multiple items with istance of same text. But we can iterate through dropdown items and then by matching exact text we can set dropdown list text selected.

Dropdownlist set selected value

In this post we will see in jquery how toset dropdown list value or selected option by it's value. For that we simply need to get object of dropdown list in jquery and then we can set selected option by using val(). of dropdownlist.

jquery dropdownlist set selected value

Example: set dropdown list selected option by value [jQuery]

<html xmlns="http://www.w3.org/1999/xhtml">
<head id="Head1" runat="server">
    <script type="text/javascript" src="https://ajax.googleapis.com/ajax/libs/jquery/1.7.1/jquery.min.js"></script>
    <title>jQuery set dropdown list selected option by value</title>
    <script type="text/javascript">
      $(document).ready(function () {
        $("#go").click(function () {
          var inputText = $("#inputText").val();
          $("#numbers").val(inputText);
        });
      });
    </script>
</head>
<body>
    <form id="form1" runat="server">
    <div>
      <label>Enter value between 1-3</label>
      <input type="text" id="inputText"/>
    <asp:DropDownList ID="numbers" runat="server">
    <asp:ListItem Text="1" Value="1"></asp:ListItem>
    <asp:ListItem Text="2" Value="2"></asp:ListItem>
    <asp:ListItem Text="3" Value="3"></asp:ListItem>
    </asp:DropDownList>
    </div>
    <input type="button" id="go" value="Go" />
    </form>
</body>
</html>

Summary: So in short we can use jquery to set dropdownlist item value like $("#numbers").val(inputText);. we can also set dropdown list selected option by using text like Set selected value by text.

Assign value to span - jquery

In this post we will see set a value to span tag using JQuer. To change value of span we can access span tag directly like $('span') and then using its .html() method we can assign some text to it.

assign value to span jquery

Example to assign text to span [jQuery]

<html xmlns="http://www.w3.org/1999/xhtml">
<head id="Head1" runat="server">
     <script type="text/javascript" src="https://ajax.googleapis.com/ajax/libs/jquery/1.7.1/jquery.min.js"></script>
    <title>Assign value to span in jQuery</title>
    <script type="text/javascript">
      $(document).ready(function () {
        $("#submitbtn").click(function () {
          var inputValue = $("#inputText").val();
          $('span').html(inputValue);
        });
      });
    </script>
</head>
<body>
    <form id="form1" runat="server">
    <div>
       <label>Type some text here to assign to span</label>
        <input type="text" id="inputText"/>
        <input type="button" id="submitbtn" value="Submit" /><br/>
        <span style="width:500px;height:120px; background-color:thistle">&nbsp;</span>
    </div>
    </form>
</body>
</html>

Summary:So to replace span tag text we get the object of span tag like $('span') and using .html() we can change value of span.

Set selected option by text of dropdownlist


In this post we will see how to set selected option by text to dropdownlist. In web application we need to set dropdownlist value at client side. By using option property of dropdown list we will check if dropdown contains text that we want to set And after that using selected attribute we will set it true so that it will show the option selected that we have set using text.
set selected option in dropdownlist using jquery

Sample to set selected option by text to dropdownlist[jQuery]


<html xmlns="http://www.w3.org/1999/xhtml">
<head id="Head1" runat="server">
    <script type="text/javascript" src="https://ajax.googleapis.com/ajax/libs/jquery/1.7.1/jquery.min.js"></script>
    <title>Set dropdownlist selected option by text</title>
    <script type="text/javascript">
      $(document).ready(function () {
        $("#go").click(function () {
         var inputText = $("#inputText").val();
          $("#numbers option:contains(" + inputText + ")").attr('selected', 'selected'); 
        });
      });
    </script>
</head>
<body>
    <form id="form1" runat="server">
    <div>
      <label>Enter value between 1-3</label>
      <input type="text" id="inputText"/>
    <asp:DropDownList ID="numbers" runat="server">
    <asp:ListItem Text="1" Value="1"></asp:ListItem>
    <asp:ListItem Text="2" Value="2"></asp:ListItem>
    <asp:ListItem Text="3" Value="3"></asp:ListItem>
    </asp:DropDownList>
    </div>
    <input type="button" id="go" value="Go" />
    </form>
</body>
</html>


Summary:By using $("#numbers option:contains(" + inputText + ")").attr('selected', 'selected'); we have dynamically set the selected option of a drop-down list using JQuery.We can set selected option of dropdown list by it's value likeset selected option of dropdown box by value