jQgrid : Custom function ajax not working

Question

I used ajax call in the custom function of jQgrid validation,

this is my function

function customFuction(value1, colname) {
    var result = null;
    $.ajax({
        url: "../ajax/check_269.php",
        type: "POST",
        data: {
            val: value1,
            col: colname,
            parentId: row_id
        },
        dataType: "html",
        async: false,
        success: function (data) {
            if (data == "error") {
                result[false, value1 + "no se permite"];
            } else {
                result[true, value1 + "Success"];
            }
        },
        error: function () {
            alert('Error trying to validate car ');
        }
    });
    return result;
}

it give me error like this

TypeError: result is null

simple query in check_269.php based on data sent by this ajax — Nisarg, Jun 28 '13 at 06:26
ajax is asynchronus... your result will be returned while the ajax call is taking place and does not wait for the ajax function to complete.. — bipen, Jun 28 '13 at 06:30
that's right, also i can't understand why are you using statement like result[boolean, string] — vladkras, Jun 28 '13 at 06:35
after assuming result as null? null is an empty object in JavaScript, so you'd better use array or (if you do really need an object) result.status and result.msg or smth like this — vladkras, Jun 28 '13 at 06:42

score 0 · Accepted Answer · answered Jun 28 '13 at 06:33

First of all the variable success are not changed inside of success callback. You should change the line

result[true, value1 + "Success"];

to

result = [true, value1 + "Success"];

and modify the line result[false, value1 + "no se permite"]; in the same way.

The main problem is that one don't need any server side validation function. If the data will be saved the server should make validation of input data. If the data are wrong the server should return some error description and some error HTTP code. If you use form editing for example then you can specify errorTextFormat callback to decode the server response in case of error. Per default jqGrid will interpret the body of the error server response as HTML fragment which will be displayed to the server.

score 0 · Answer 2 · answered Jun 28 '13 at 06:33

ajax is asynchronus.. the reason you are getting null is because bythetime ajax call is completed the function will return the result as null and doesn't wait for ajax call to complete..

one way around is to return the result inside the success callback function of ajax to make sure ajax call completes.

 function customFuction(value1, colname) {
var result = null;
$.ajax({
    url: "../ajax/check_269.php",
    type: "POST",
    data: {
        val: value1,
        col: colname,
        parentId: row_id
    },
    dataType: "html",
    async: false,
    success: function (data) {
        if (data == "error") {
            result = [false, value1 + "no se permite"];
        } else {
            result = [true, value1 + "Success"];
        }
         return result;
    },
    error: function () {
        alert('Error trying to validate car ');
    }
});

}

and i guess you missed = to set the result array.

jQgrid : Custom function ajax not working

2 Answers2