<p>I always see the code like this in the blogs: </p>

<pre><code>$.ajax({
                    type: "POST",
                    contentType: "application/json; charset=utf-8",
                    url: "WebService.asmx/HelloWorld",
                    data: "{}",
                    dataType: "json",
                    success: function(msg) {
                        alert(msg.d);
                    }
                });
</code></pre>

<p>But I think this is run only with asp.net 3.5. I couldn't run it with 2.0. How can I use such these codes in my Applications? </p>

I already know this article, but It couldn't help me.
In my sample app, I use these codes:
my Jquery code:
```
```
$(document).ready(function() {            
        $('#clKaydet').click(function() {
            $.ajax({
                type: "POST",
                contentType: "application/json; charset=utf-8",
                url: "WebService.asmx/HelloWorld",
                data: "{}",
                dataType: "json",
                success: function(msg) {
                    alert(msg);
                }
            });

        });

    });
```
```
My Html Code:
```
```
<form id="form1" runat="server">
    <asp:ScriptManager ID="ScriptManager1" EnablePageMethods="true" runat="server" />
    <div>

        <input type="button" id="clKaydet" runat="server" value="Kayıt" onclick="Kayit()" />
    </div>

    </div>
    </form>
```
```
My Webservise Code:
```
```
<WebMethod()> _
Public Function HelloWorld() As String
    Dim sText As String = "Hello"
    Return sText
End Function
```
```
Is there any mistake?