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JavaScript

Posted by Hossam Khalifa
Hossam Khalifa
17,200 Points

Javascript looping problem

This is some code that loops through an array containing links that should be opened in a new window The following code starts opening the first window while adding it as an objects in the "windows" empty object.

 var link = document.querySelectorAll("a.title");
var windows = {};
windows["wind" + 0 ] =  window.open(link[1].href);
windows["wind" + 0 ].onload =function(){
windows["wind" + 0 ].location.href = $(windows["wind" + 0 ].document.getElementsByClassName("rss-link")).attr("href");}
var i = 1;

This is the function that should be done every loop and the loop

function download () {
            windows["wind" + (i-1) ].onload = function(){

            windows["wind" + i ] =  window.open(link[i].href);

            windows["wind" + i ].onload = function(){

                windows["wind" + i ].location.href = $(windows["wind" + i ].document.getElementsByClassName("rss-link")).attr("href");

            }
}
    }
    while(i<link.length){
download();
i++;
}

This the error I get : Uncaught TypeError: Cannot set property 'onload' of undefined

And the windows object looks like this

windows = {wind0: Window, wind2: Window}

Please help

3 Answers

Hossam Khalifa
Hossam Khalifa
17,200 Points
Hossam Khalifa
Hossam Khalifa
17,200 Points

Any answers ??

Vittorio Somaschini
Vittorio Somaschini
33,371 Points
Vittorio Somaschini
Vittorio Somaschini
33,371 Points

Hello Hossam.

I am having troubles understanding your question, but a couple of things that you can do may help me.

1) on which line is the error (according to javascript console)?

2) can you please write an example of how you want your output to be?

ty

Vittorio

Hossam Khalifa
Hossam Khalifa
17,200 Points

The error is on the first onload event in the download function And the output should be windows that get opened after the other one have finished loading and the links are in the links array on line 1

Hossam Khalifa
Hossam Khalifa
17,200 Points

The error is on the first onload event in the download function And the output should be windows that get opened after the other one have finished loading and the links are in the links array on line 1

Jeff Everhart
Jeff Everhart
21,732 Points
Jeff Everhart
Jeff Everhart
21,732 Points

I don't think your windows object is valid JSON. You need quotation marks around the keys and values: http://json.org/example

Hossam Khalifa
Hossam Khalifa
17,200 Points

The windows object looks like this after the loop has finished I mean it does not create a wind1 property of the windows object and I don't know why