Calling method from code behind by jquery ajax

when i will call any server side method by jquery and if that server side method return nothing means void then how my jquery ajax code will look like ?

here a sample jquery ajax call code

var fname = _TrackNumber + '.gif';
var DTO = { FileName: fname };

jQuery.ajax({
            type: "POST",
            url: "UPSLabelFormUK.aspx/SaveAs",
            data: JSON.stringify(DTO),
            contentType: "application/json; charset=utf-8",
            dataType: "json",
            success: function (data) {
                var retVal = data.d;
                alert(retVal);
            },
            error: function (XMLHttpRequest, textStatus, errorThrown) {
                alert(textStatus);
            }
        });


this is my server side code....it return void

 [WebMethod]
        public static void SaveAs(string FileName)
        {
 // code here
        }

so tell me my jquery ajax call routine parameter is ok....or do i need to change anything.

i feel i need to change something in this code like below

            contentType: "application/json; charset=utf-8",
            dataType: "json",
            success: function (data) 
 {

i think contentType & dataType will need to remove from ajax call routine. success function will not have any argument.

please tell me am i right....if not then please rectify my code. thanks

Re: Calling method from code behind by jquery ajax

when server method returns void to jquery ajax call, data parameter in success event will be set to null

contentType: "application/json; charset=utf-8", -- this indicates the type of content which is being sent from client to server. keep it as is
dataType: "json", -- indicates type of respose from server. you can avoid this parameter if return value is null.
success: function (data) -- data.d will give you javascript null value. so the alert will display null

hope this helps...

Re: Calling method from code behind by jquery ajax

Hi,

If you are trying to upload a file using jQuery and pagemethod, Its not possible. You can look into some plugin here-

http://forums.asp.net/p/1742691/4697039.aspx/1?Re+Posting+Forms+in+Jquery+and+asp+net

http://delicious.com/anupdg/upload