Question

I have the following ajax email submit routine on my ASP.NET WebForms web site:

A page provides a user with an input dialog, where he enters data.
A data is packed into a json like this:

        var name = $("[id$='clientName']");
        var phone = $("[id$='clientPhone']");
        var serviceType;
        var serviceCost;

    $("#SubmitOrder").click(function () {

        var currName = name.val();
        var currPhone = phone.val();

        var json = "{'ClientName':'" + escape(name.val()) + "','ClientPhone':'" + escape(phone.val()) + "','ServiceType':'" + serviceType + "','ServiceCost':'" + serviceCost + "'}";
        var ajaxPage = "/sendmail.aspx?Send=1"; 
        var options = {
            type: "POST",
            url: ajaxPage,
            data: json,
            contentType: "application/json;charset=utf-8",
            dataType: "json",
            async: true,
            success: function (response) {                  
                $("#ResMsg").html(response);
            },
            error: function (msg) { alert("failed: " + msg); }
        };

        $.ajax(options);
    });

and is sent to a sendmail.aspx for procession. sendmail.aspx is just a webforms page that, when debugged, works just fine. It receives and parses the JSON correctly, then initiates an async mail sending routine.

protected void Page_Load(object sender, EventArgs e)
    {
        if (!IsPostBack)
            SendMail();
    }

private void SendEmail()
    {
        //Bunch of parsing and mail sender init

        mailSender.MessageSent += new MessageSentEventHandler(OnMessageSent);
        //Here we have subscribed to an async event that occurs when mail sender is done.

        // Other unimportant stuff

        mailSender.SendMessage(settings["mail.feedback.to.name"], settings["mail.feedback.to.email"], settings["mail.feedback.subject"], body);
    }

void OnMessageSent(object sender, MessageSentEventArgs args)
    {
        if (args.Status == MailSentStatus.Sent)
        {
            Response.Write("Everything is fine"); 
        }
        else
        {
            Response.Write("Oops. Error!"); 
        }
    }

The problem:

On my client page, whenever the response is received from the mail sender I get a

failed: [object Object] message box.

Apparently my error: method gets executed instead of success:. But the mail sender sends messages just fine.

What is the correct way to respond to a jquery .ajax() call from an ASP.NET? What am I doing wrong in my case?

Answer 1

You told $.ajax to expect dataType: "json", so it’s trying (and failing) to parse the returned HTML as JSON.