Question

Can someone help me to understand the process in the following link, especially part within onClick:

<a href="http://www.example.com/files/download/files.php?file=my_file.doc" onClick="_gaq.push(['_trackEvent', 'Downloads', 'DOC', this.href.substr(23)]); fn12_reminder(this,''); return false;" rel="nofollow">

I understand that this is simple GA even tracking process, but what I cannot understand is the last part this.href.substr(23) I cannot figure out what this actually does in the entire process?

the js script loaded in the header is of the following nature (I am posting it in full, so that someone with experience can spot a connection, if one exists):

var functions = true;
function fn12_custom_display_notice(theNotice,theClass){
    if(theClass!=''){
        jQuery("#user-notice").removeClass();
        jQuery("#user-notice").addClass(theClass);
        }
        jQuery("#user-notice").html(theNotice).animate({width:'toggle'},250).delay(3000).animate({width:'toggle'},250);
        }
function fn12_custom_display_reminder(theHTML,theDownloadLink){if(typeof jQuery.ui!='undefined'){$("#dialog").attr("title","Please help spread the word").html(theHTML);$("#dialog").dialog({modal:true,width:375,buttons:{"Continue to Download":function(){$(this).dialog("close");window.location=theDownloadLink;}}});}else{window.location=theDownloadLink;}}
function fn12_custom_reminder(aelem,topic){theLink=$(aelem).attr("href");$.ajax({type:"POST",url:"/db/ajax.php",data:"action=reminder&thepath="+theLink+"&topic="+topic,dataType:"json",error:function(){window.location=theLink;},success:function(msg){if(msg.status==1)fn12_custom_display_reminder(msg.html,theLink);else{fn12_custom_display_notice(msg.message,"error");}}});}
function fn12_custom_gplus_callback(theObject){if(theObject.state=='on'){fn12_custom_display_notice("Big thanks!!!",'success');}}

/* jquery_cookie.js Copyright (c) 2006 Klaus Hartl (stilbuero.de), Dual licensed under the MIT and GPL licenses */
jQuery.cookie=function(name,value,options){if(typeof value!='undefined'||(name&&typeof name!='string')){if(typeof name=='string'){options=options||{};if(value===null){value='';options.expires=-1;}
var expires='';if(options.expires&&(typeof options.expires=='number'||options.expires.toUTCString)){var date;if(typeof options.expires=='number'){date=new Date();date.setTime(date.getTime()+(options.expires*24*60*60*1000));}else{date=options.expires;}
expires='; expires='+date.toUTCString();}
var path=options.path?'; path='+(options.path):'';var domain=options.domain?'; domain='+(options.domain):'';var secure=options.secure?'; secure':'';document.cookie=name+'='+encodeURIComponent(value)+expires+path+domain+secure;}else{for(var n in name){jQuery.cookie(n,name[n],value||options);}}}else{var returnValue={};if(document.cookie){var cookies=document.cookie.split(';');for(var i=0;i<cookies.length;i++){var cookie=jQuery.trim(cookies[i]);if(!name){var nameLength=cookie.indexOf('=');returnValue[cookie.substr(0,nameLength)]=decodeURIComponent(cookie.substr(nameLength+1));}else if(cookie.substr(0,name.length+1)==(name+'=')){returnValue=decodeURIComponent(cookie.substr(name.length+1));break;}}}
return returnValue;}};

Any help is highly appriciated

Answer 1

In your example, this.href.substr(23) is equal to files/download/files.php?file=my_file.doc, it’s simply the url associated with the a element.

• this refers to the current object, the a element.
• href refers to the element’s attribute.
• substr(23) takes the substring starting on the 23rd character, to strip the protocol and domain name.