This function is an easy way to call a URL and receive an evaluated JSON response. You can pass POST data to the server either as a parsed JSON object or as a raw POST buffer.

JSON Parameter (just pass a value):

function CallService()
{
    ajaxJson("services/timetrakkerservice.svc/LoadCustomer",
         {Pk:12,Entered:new Date()},         
         function (result)  // parsed object instance
         {
             alert( result.d.Company);
             alert( result.d.ProjectEntities[1].CustomerEntity.LastName);
         },onError);

function onError(error)  // error object
{
    alert("Error: " + error.message);
}

Raw POST data:

function CallService()
{
    ajaxJson("services/timetrakkerservice.svc/SaveCustomer",
         "Name=Rick&Company=West+Wind",
         Callback,onError,
         { contentType: "application/x-www-urlencoded"});
}
function Callback(result)
{
    alert( result.d.Company);
    alert( result.d.ProjectEntities[1].CustomerEntity.LastName);
}
function onError(error)
{
    alert("Error: " + error.message);
}

Note that if passing a string you should pass the content type explicitly - otherwise the string will be posted as JSON.

If you are calling a CallbackHandler or AjaxMethodCallback control on the server use the ajaxCallMethod function instead.