JavaScript - referencing 'this' in an inner function

Question

Consider the following code:

MyClass.prototype.my_func = function () {
    this.x = 10;
    $.ajax({
        // ...
        success: function (data) {
                   


        

Answer 1

the this syntax usually refers to the object, not a function. In your case, this refers to MyClass.

If you're using the variable in the object, you probably forgot to define x in MyClass.

If you're using the variable within the function ONLY I'd define my variables using the var syntax. Variables defined within a function are destroyed when a function ends.

MyClass.prototype.my_func = function () {
    var x = 10;

    $.ajax({
        // ...
        success: function (data) {
            alert(x);
        }
    });
}