Override js alerts failing

Asked Jun 03 '16 at 07:57

Active Jun 03 '16 at 08:17

Viewed 38 times

I am trying to override the JS alerts so I can do some stuff before and after each alert. This is what I wrote:

var old_alert = alert
var alerting = false
    function alert(message) {
      alerting = true;
      console.info("alert override: alerting");
      var result = old_alert(message);
      alerting = false;
      console.info("alert override: done alerting");
      return result;
  }

The problem I'm facing is that old_alert somehow points to my new function and I get an infinite recursion error from my browser. What am I doing wrong?

asked Jun 03 '16 at 07:57

Mario Stoilov

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i believe you have to return false or something like that. Return a value that stops the default execution – Stian Standahl Jun 03 '16 at 07:59
have you tried overriding the alert like in this answer http://stackoverflow.com/a/1729684/582061 ? – Stian Standahl Jun 03 '16 at 08:01
@StianStandahl I am unable to use jQuerry in my project (as per that answer suggests) – Mario Stoilov Jun 03 '16 at 08:03
how about just doing this: window.alert = function(){ //do something } . note i am looking for a way to handle default behavior from inside this function – Stian Standahl Jun 03 '16 at 08:06
here you go. http://stackoverflow.com/a/10427741/582061 note: IE8 throws exception – Stian Standahl Jun 03 '16 at 08:07
well, that helped. Should mark this as a duplicate – Mario Stoilov Jun 03 '16 at 08:14

Override js alerts failing

0 Answers0