Calling Server Side Function Using Javascript

Calling Server Side Function Using Javascript

Many of us needs a server side function to be called from JavaScript. We can do this easily using __doPostBack

as

Javascript Code

function CallServerCode()

{

__doPostBack('btnTest', '');

}

and in HTML

<­button type="­button" onclick="javascript:CallServerCode();">Call Server Code<­/­button­>

<­asp­:­linkbutton id="btnTest" runat="server" text="ASP .Net Button"­> <­/­asp­:­linkbutton>

and the Server side code

Protected Sub btnHidden_Click(ByVal sender As Object, ByVal e As System.EventArgs) Handles btnTest.Click

Response.Write("Hello")

End Sub

Now note that whenever the client button with caption "Call Server Code" will be clicked it will call Serverside event of btnTest using Javascript.

Alternative Approach:

In design :
In the head section:

 <script type="text/javascript" language="javascript">

    function callme(chkCall)

    {

       var chkCall=document.getElementById(chkCall);

       if(chkCall.checked==true)

        {

             chkCall.checked=true;

             PageMethods.GetContactName();

        }

        else

        {

              chkCall.checked=false;

        }

    }

    </script>

In the body section:

<asp:ScriptManager ID="ScriptManager1" runat="server" EnablePageMethods="true" />

<asp:CheckBox ID="chkCall" runat="server" />

In the CS part :

protected void Page_Load(object sender, EventArgs e)

    {

        chkCall.Attributes.Add("onclick", "javascript:callme('" + chkCall.ClientID + "')");

    }

    [System.Web.Services.WebMethod]

    public static void GetContactName()

    {

        Response.Write("your name");

    }