Question

I’m using Andrew Valums’ Ajax Upload plugin (GitHub link). Here is some code from it:

qq.getUniqueId = (function(){
    var id = 0;
    return function(){ return id++; };
})();

It’s kind of a long story, but I’m in a situation where, under certain circumstances, I’d like the qq.getUniqueId function to start with an ID other than 0. It can still increment by one; it just has to start with something other than 0. What’s the best way to do that?

Here are the steps to create a test environment:

1. Download the plugin: http://github.com/valums/file-uploader/zipball/master

2. Unzip it and move the “client” folder onto a web server.

3. Open the “demo.htm” file in a text editor, search for action: 'do-nothing.htm', and add onComplete: function(id, fileName, responseJSON) {alert(id)}, right after that.

4. Open the “demo.htm” file in a web browser. Be sure to access it through a web server (as opposed to just opening the local file) or else it won’t work.

5. Upload a file. It should alert a “0” after the upload finishes. See if you can modify it so that I can pass in a different starting number.

Thanks!

Answer 1

Try replacing the function with one that calls the original, but adds an offset:

function offsetUniqueId(n) {
   var old = qq.getUniqueId;
   qq.getUniqueId = function() {
       return old() + n;
   }
}

See http://jsfiddle.net/alnitak/gWjqX/