无效的JSON响应？

I have a page that does some stuff and then outputs a JSON response. This page is called from a jQuery Ajax call but when I inspect the post in Firefox I get Invalid JSON which I do not understand.

Here is the code of the page

Write("{status: 'ERROR', StatusCode: '" + result.StatusCode + "',payload: ''}");

The output looks like this (looks right to me?)

{status: 'ERROR', StatusCode: '200',payload: ''}

Here is my AJAX Call

$.ajax({
            type:"POST",
            url: copyBUURL,
            data: { action: "copy_bu", bu_id: selected_bu.id, bu_name: selected_bu.name, new_parent: new_parent_bu.id, new_parent_name: new_parent_bu.name, new_name: $("#bu_name").val(), from_name: $("#bu_fromname").val(), email: $("#bu_email").val() },
            contentType:"application/x-www-form-urlencoded; charset=utf-8",
            dataType:"json",
            success:function(data){
                if(!data)
                {
                    alert("There was an error processing your request");
                    return false;
                }
                $("#createBtn").removeAttr("disabled");
                $("#cancelBtn").removeAttr("disabled");

                console.log("Data response: " + JSON.stringify(data));

                //xhr_users Landing Page
                showUrlInDialog('https://pages.umusic-mail.com//page.aspx?QS=472529ec60bdf32a5a46a47dceedf4ab0793800df7757ecbd2298ad0f8bc85eb&bu_id=' + data.bu_id + '&bu_name=' + data.bu_name);

                if (data.status == "OK") {

                    $("#msgBox").css("height", "80px");
                    $("#result").html("The Business Unit was successfully copied!<br /><br />Users will be assigned very shortly. (You will see a dialog window pop up in this page).");
                    $("#loader").attr("src", "https://dl.dropbox.com/u/417891/aeg-checkmark.png").css("display", "inline");
                    hideContainer();
                    resetForm();
                    $("#business_units").jstree("refresh");
                } else if (data.status.toUpperCase() == "ERROR") {
                    displayError(data.payload);
                    $("#msgBox").attr("class", "msgBoxOff");
                    $("#result").html("");
                    $("#loader").css("display", "none");
                } else {
                    // something way wrong
                }
            },
            error: function (xhr, ajaxOptions, thrownError) {
                console.log(xhr.status);
                console.log(thrownError);
            }
        });

You need to have double quotes around everything like this:

{
    "status": "ERROR",
    "StatusCode": "200",
    "payload": ""
}

Or this:

{
    "status": "ERROR",
    "StatusCode": 200,
    "payload": ""
}

If you want StatusCode to be an integer.
Also, consider using JSONLint to validate your json if you have future problems.