Scope of the jquery ajax success callback?

if I have

function AjaxRequest(){
    var testvar = 0;
    for(i=0;i<d.length;i++){
        $.ajax({
            success: function(a){
 开发者_高级运维               testvar++;
            }

        });
    }
}

Will testvar increase on success?

Yes; the variable is captured by the function's closure.
Closures keep variables alive so that nested functions can still use them later.

Note that the success callbacks only run some time after the rest of your code finishes (AJAX is asynchronous).

Yes, it will. It's similar to this:

function() {
   var self = this;
    this.a = function(){
        self.something;
    }
}