Ladysign

Javascript GET URL parameters

Difficulty:

This Javascript function I’ve used a lot. Retrieve URL GET parameters with Javascript.
(For example:
http://www.theUrl.nl/script.html?parameterX=100&parameterY=200)

	/**
	 * Get URL parameters
	 * @param the name of the parameter from the URL to retrieve
	 * @return the requested parameter value if exists else an empty string
	 */
	function getUrlParam(name) {
		var regexS;
		var regexl;
		var results;

		name = name.replace(/[\[]/,"\\\[").replace(/[\]]/,"\\\]");
		regexS = "[\\?&]"+name+"=([^&#]*)";
		regex = new RegExp(regexS);
		results = regex.exec (window.location.href);
                //note: don't write space after command exec

		if ( results == null ) {
			return "";
		} else {
			return results[1];
		}
	}

To show you the example with the previous given URL:

/* this will output the string 200, in an alert popup box */
alert(getUrlParam(parameterY));