Working with JsonHTTPHandler

Introduction

This little code just gives you hands on trick to access Webservice using JavaScript.

Background

I knew that webservice can be accessed by JavaScript, but haven't thought that there was such an easy way. Have a look at it.

Using the Code

Let's start step by step.

Step 1

Add Script Manager Instance to your ASPX Page. Here I have specified path of my webservice (QuoteService.asmx).

<asp:ScriptManager ID="_ScriptManager" runat="server">
            <Services>
                <asp:ServiceReference Path="~/QuoteService.asmx" />
            </Services>
        </asp:ScriptManager>

Step 2

Add the below mentioned attribute to your code behind of Webservice (in my case QuoteService.cs)

[WebService(Namespace = "http://tempuri.org/")]
[WebServiceBinding(ConformsTo = WsiProfiles.BasicProfile1_1)]
[ScriptService]

And write some method to your Webservice Code Behind Class. (In my case QuoteService.cs)

[WebMethod]
public string GetQuote(int intVar)
{
return (intVar + 6).ToString();
}

Step 3

Call a Function from JavaScript and define the Return value handler of function.

function LookUp() {
            QuoteService.GetQuote(2, OnLookupComplete)
        }

Define result Handler Function as depicted in the above code.

function OnLookupComplete(result) {
            alert(result);
        }

So guys, we are done with our tricks.

Points of Interest

I just was thinking it will be a very time consuming concept to calling webservice from JavaScript, but as I searched through net, I found a very simple solution, so I thought it may be useful to you also in some part of code.