Pro PHP and jQuery by Jason Lengstorf.pdf - Computer Science ...

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CHAPTER 7 ■ ENHANCING THE USER INTERFACE WITH JQUERY
/.*?\?(.*)$/
Regular expressions in JavaScript are delimited by forward slashes (/) at each end of the expression.
Inside this expression, the pattern looks for zero or more of any character (from left to right) until the
first time it reaches a question mark; it then stores all characters after the question mark until the end of
the string as a named group for use in the replacement.
■ Note You’ll learn much more about regular expressions and how they work in Chapter 9.
Incorporating a Regular Expression into a Script
You want to extract the href value of the link that was clicked, so you’ll use the this keyword. In order to
use jQuery methods, you have to pass this as the selector to the jQuery function first. Now access the
href value with the .attr() method, then call .replace() and extract the query string.
When using regular expressions in .replace(), no quotes are used to enclose the pattern. Using the
regular expression just described, modify init.js to store the query string from the clicked link in a
variable called data; do this by adding the code shown in bold:
// Makes sure the document is ready before executing scripts
jQuery(function($){
// Pulls up events in a modal window
$("li>a").live("click", function(event){
// Stops the link from loading view.php
event.preventDefault();
// Adds an "active" class to the link
$(this).addClass("active");
// Gets the query string from the link href
var data = $(this)
.attr("href")
.replace(/.+?\?(.*)$/, "$1");
// Logs the query string
console.log( data );