Why does $.ajax call for json data trigger the error callback when http status code is “200 OK”?

Question

I have the following ajax request:

        jQuery.ajax({
            async: true,
            type: \"GET\",
            url: url,
            data: data,
           


        

Answer 1

I do a lot of testing with file: urls instead of using a web server. My JSON code will always have the wrong MIME type. To take care of this I use the following code:

$(document).ready(
    function (){

        myData = {};
        $.ajax({
            type: "GET",
            // url: "json.php?fn=jsonData.json",        // with Apache
            url: "jsonData.json",                       // As a file:/// URL
            contentType: "application/json; charset=utf-8",
            data: myData,
            beforeSend: function(x) {
                if(x && x.overrideMimeType) {
                    x.overrideMimeType("application/json; charset=UTF-8");
                }
            },
            dataType: "json",

            success: function(returnData){
                 $("#jsonData").html("Success:"+returnData.tag);
            },
            error: function(returnData) {
                 $("#jsonData").html("Error:"+returnData.tag);
            }
        });
    }
);

This will force the MIME type to be correct for JSON data.