Delay all ajax requests

Question

Uncaught TypeError: Illegal invocation

I'm having this error when trying delay all ajax requests in my application.

(function(send) {
  XMLHttpRequest.prototype.send = function(data) {
    setTimeout( function () {
      send.call(this, data); //Error here
    },3000);
  };
})(XMLHttpRequest.prototype.send);

Could you give me some hints? Thanks in advance.

Possible duplicate of [Why are certain function calls termed "illegal invocations" in JavaScript?](http://stackoverflow.com/questions/10743596/why-are-certain-function-calls-termed-illegal-invocations-in-javascript) — Christoph, May 09 '17 at 15:54
@fluis save it into a variable like: `var _this = this` before calling `setTimeout` — Abhi, May 09 '17 at 15:58
Possible duplicate of [How to access the correct \`this\` inside a callback?](http://stackoverflow.com/questions/20279484/how-to-access-the-correct-this-inside-a-callback) — Andreas, May 09 '17 at 16:02

MattSizzle · Accepted Answer · 2017-05-10T19:06:50.600

0

It seems you are calling .call passing in the current scope which would be window.

(function(send) {
  XMLHttpRequest.prototype.send = function(data) {
    var self = this;
    setTimeout( function () {
      send.call(self, data); //Updated `this` context
    },3000);
  };
})(XMLHttpRequest.prototype.send);

edited May 10 '17 at 19:06

answered May 09 '17 at 15:55

MattSizzle

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_"which would be setTimeout function"_ No -> `this === window` – Andreas May 09 '17 at 16:00

Delay all ajax requests

1 Answers1