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POJS Variable Scope
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copied!<p>Variable scope in JS is confusing the hell out of me. In follwing code, if i use the setClient public method to set a clientID i can then access the value from inside the track method using the getClient method. I cannot however access the value of the private member 'version' this way (or any other private member).. i had assumed that var _this = this would create a closure of some sort allowing access to the scope of the Container function.</p> <p>And now i'm confused. I realise this is probably really simple though, so I thought i'd ask here. Where on earth have a grasped the wrong end of the stick?</p> <pre><code>function Container() { // private members var version = '0.1'; var CID = false; var _this = this; // public members this.getVersion = function() { return _this.version; } this.getClient = function() { return _this.CID; } this.setClient = function(CID) { _this.CID = CID; } // private methods this.getQS = function() { return _this.version; } // public methods this.track = function() { if (_this.CID) { var date = new Date(); data = { cid: _this.getClient(), sw: screen.width ? screen.width : false, sh: screen.height ? screen.height : false, d: date.getTime() } qs = ''; for (p in data) { qs += p+'~'+data[p]+'-'; } var elHd = document.getElementsByTagName("head")[0]; var elScr = document.createElement('script'); elScr.type = 'text/javascript'; elScr.src = 'http://example.org/'+qs+ 'version-'+_this.getVersion(); elHd.appendChild(elScr); } else { alert('no client ID'); } } } </code></pre>

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