Replace a parameter in a query string

index.js

function paramReplace(name, string, value) {
	// Find the param with regex
	// Grab the first character in the returned string (should be ? or &)
	// Replace our href string with our new value, passing on the name and delimeter

	var re = new RegExp("[\\?&]" + name + "=([^&#]*)");
	var matches = re.exec(string);
	var newString;

	if (matches === null) {
		// if there are no params, append the parameter
		newString = (string.indexOf('?') > 0)? string + '&': string + '?';
		newString += name + '=' + value;
	} else {
		var delimeter = matches[0].charAt(0);
		newString = string.replace(re, delimeter + name + "=" + value);
	}
	return newString;
}