.NET syntax of responsestring to match JS-callback function with multiple parameter

Question

Hi,

i would like to pass multiple parameters in my callback function and don't know who to do this...

This would be the C# code:

        Response.Clear();
        Response.ContentType = "text/plain";
        Response.Write("content of param1");
        Response.Write("content of param2");
        Response.End();

and the JS code:

    $.getJSON("localhost/myFunction", dataString,
        function(param1, param2) {
           alert(param1);
           alert(param2);
        });

How would i perform the actual mapping of parameter in the C# code, so JavaScript recognizes them as the 2 parameters of the callback function? ( In detail i want to pass a JSON-object and a "status" parameter here... )

Answer 1

Send the parameters as a JSON encoded object:

Response.ContentType = "application/json";
Response.Write("{ param1: 'value1', param2: 'value2' }");

And in javascript:

$.getJSON('localhost/myFunction', dataString,
    function(json) {
        alert(json.param1);
        alert(json.param2);
});

Answer 2

There is a proper way to do this, and I'm sure you'll find it quite convenient, so I'll show you that instead of hacking away at what you've got to make it work:

Create a webservice file (asmx) in your website. In the cs (or vb) file that's created, just above the class declaration, there's a ScriptService attribute that's commented out. Uncomment it, so that you can access the service from script.

Create a new method that returns the values in an object (anonymous types will do). Note the WebMethod attribute:

[WebMethod]
public object MyFunction() {
    return new {
        status = "Status string",
        jsobj = new {
            childParam = "complex object",
            childArray = new[] { "holds", "any", "values", "convertible", "to", "js" }
        }
    };
}

You can now make an AJAX call to this method, from your code, like so:

$.ajax({
    type: 'POST',
    url: 'MyService.asmx/MyFunction',
    contentType: 'application/json; charset=utf-8',
    dataType: 'json',
    data: '{}',
    success: function(res) {
        alert(res.status);
        alert(res.jsobj.childParam);
    }
});

This way, .NET will take care of the JSON serialization for you, and you won't have to worry about escaping characters within your return values etc.