Extend Callback with parameters

Question

Assuming I have a method wrapping the jQuery ajax method:

function GetJson(url, completeCallback, alwaysCallback, failCallback) {   
var newUrl = location.protocol + "//" + location.host + url;

$.getJSON(newUrl).done(function (result) {
    if (typeof completeCallback == "function") {
        completeCallback(result);
    }                
}).fail(function (jqxhr, textStatus, error) {
    if (typeof failCallback == "function") {
        failCallback(result);
    } else {
        alert("Request failed for " + url + " textStatus:" + textStatus + " Error:" + error);
    }        
}).always(function () {
    if (typeof alwaysCallback == "function") {
        alwaysCallback();
    }        
}); }

And i call the DoSomething method, which internally calls GetJson. The result from the GetJSON callback I want to pass as the first parameter of DoResume; the remaining arguments should be passed from the methods signature.

function DoSomething(a, b, c, id) {
var url = '/MyController/GetData?id=' + id;    
GetJson(url, DoResume(this.Result, a, b, c)); }

function DoResume(result, a, b, c) { }

I tried to achieve this using this keyword, but the result is not assigned.

One wonders why you have such a wrapper for $.getJSON - it seems you're hiding away the new-style promises and returning to using the likes of the success and error options you can pass to the core $.ajax function. — James Thorpe
– James Thorpe, Commented Aug 8, 2016 at 15:38
Thx! Yes, i know, it is very bad style. I will refactor this later to use promises, for now, i just need to get the stuff working in a short time frame ;-( — NickD
– NickD, Commented Aug 8, 2016 at 15:56

Yury Tarabanko · Accepted Answer · 2016-08-08 15:36:44Z

3

You need to pass a function not the result of its invocation

GetJson(url, function(result){
    DoResume(result, a, b, c);
});

answered Aug 8, 2016 at 15:36

Yury Tarabanko

45.1k10 gold badges88 silver badges99 bronze badges

Sign up to request clarification or add additional context in comments.

Comments

AaronK · Accepted Answer · 2016-08-08 15:42:13Z

1

In your example, you are not passing DoResume into SendJSON, you're calling DoResume, then passing its result. You need to pass a function instead.

SendJSON( url, null, function( result ) {
    DoResume( result, a, b, c );
} );

answered Aug 8, 2016 at 15:42

AaronK

215 bronze badges

Collectives™ on Stack Overflow

Extend Callback with parameters

2 Answers 2

Comments

Comments

Your Answer

Hot Network Questions

Collectives™ on Stack Overflow

2 Answers 2

Comments

Comments

Your Answer

Sign up or log in

Post as a guest

Related