doPlugins Function

JavaScript plug-ins are usually called by the doPlugins function, which is executed when the t() function is called in the Code to Paste.

Consequently, if you set a variable in the doPlugins function, you may overwrite a variable you set on the HTML page. The only time the doPlugins function is not called is when the usePlugins variable is set to false.

Code Example

The doPlugins function is typically called s_doPlugins. However, in certain circumstances (usually when more than one version of Analytics code may appear on a single page), you can change the doPlugins function name. If the standard doPlugins function needs to be renamed to avoid conflicts, assign doPlugins the correct function name, as shown in the example below.

/* Plugin Config */
s_mc.usePlugins=true
function s_mc_doPlugins(s_mc) {
/* Add calls to plugins here */
}
s_mc.doPlugins=s_mc_doPlugins

Using doPlugins

This function provides an easy way to give default values to variables, or to take values from query string parameters on any page of the site. Using doPlugins can be easier than populating the values in the HTML page, because only one file must be updated. Changes to the JavaScript file are not always immediate. Return visitors to your site are often using cached versions of the JavaScript file. Meaning, updates to the file may not be applied to all visitors for up to one month after the change is made.

The following examples show how you can use the doPlugins function to set a default value for a variable and to get a value from the query string.

/* Plugin Config */
s.usePlugins=true
function s_doPlugins(s) {
/* Add calls to plugins here */
// if prop1 doesn't have a value, set it to "Default Value"
if(!s.prop1)
s.prop1="Default Value"

// if campaign doesn't have a value, get cid from the query string
if(!s.campaign)
s.campaign=getQueryParam('cid');
}
s.doPlugins=s_doPlugins

Installed Plug-ins

To find out whether a plugin is included in your JavaScript file and ready for use, look in the Plugins Section of the JavaScript file. The following example shows what the getQueryParam function looks like in the Plugins Section.

/************************** PLUGINS SECTION *************************/

/* You may insert any plugins you wish to use here. */
/*
* Plugin: getQueryParam 1.3 - Return query string parameter values
*/
s.getQueryParam=new Function("qp","d",""
+"vars=this,v='',i,t;d=d?d:'';while(qp){i=qp.indexOf(',');i=i<0?qp.l"
//
// ... more code below ...
//