Answers for "how to get the errors form ajax"

ajax error get output

$.ajax({
    type:     "post",
    data:     {id: 0},
    cache:    false,
    url:      "doIt.php",
    dataType: "text",
    error: function (request, error) {
        console.log(arguments);
        alert(" Can't do because: " + error);
    },
    success: function () {
        alert(" Done ! ");
    }
});

ajax jquery errors

$.ajax({
    url: 'some_unknown_page.html',
    success: function (response) {
        $('#post').html(response.responseText);
    },
    error: function (jqXHR, exception) {
        var msg = '';
        if (jqXHR.status === 0) {
            msg = 'Not connect.\n Verify Network.';
        } else if (jqXHR.status == 404) {
            msg = 'Requested page not found. [404]';
        } else if (jqXHR.status == 500) {
            msg = 'Internal Server Error [500].';
        } else if (exception === 'parsererror') {
            msg = 'Requested JSON parse failed.';
        } else if (exception === 'timeout') {
            msg = 'Time out error.';
        } else if (exception === 'abort') {
            msg = 'Ajax request aborted.';
        } else {
            msg = 'Uncaught Error.\n' + jqXHR.responseText;
        }
        $('#post').html(msg);
    },
});