jquery性能优化手册（The performance optimization of jQuery manual）.docVIP

jquery性能优化手册（The performance optimization of jQuery manual） Now more and more jQuery applications, some of my classmates were enjoying a refreshing coding will ignore the dripping performance, problems such as me. Although jQuery in many of the JS libraries in performance is good, but not used JavaScript in the development of primary, performance problems still need attention. jQuery Performance Rules this article. In twitter, a simple translation: Always inherits from the ID selector Using tag before class Cache the jQuery object Have a strong chain operation Using subquery Restrict direct DOM operation Bubble Elimination of invalid queries Defer to $(window).Load Compressed JS Fully grasp the jQuery Library 1. always inherits from the ID selector The fastest selector in jQuery is the ID selector because it comes directly from the getElementById () method of the Javascript div id= content form method=, post, action= / h2Traffic Light/h2 ul id= traffic_light liinput type= radio class= on name= light value= red Red/li liinput type= radio class= off name= light value= yellow Yellow/li liinput type= radio class= off name= light value= green Green/li /ul input class= button id= traffic_button type= submit value= Go / /form /div Choosing buttons like this is inefficient: Var traffic_button = $(#content,.Button); The direct selection button with ID is more efficient: Var traffic_button = $(` #traffic_button ); Select multiple elements When it comes to multi element selection, youre actually talking about DOM traversal and loops. These are slower things. In order to improve performance, its better to start with the nearest ID Var traffic_lights = $(#traffic_light, input); 2. use tag before class The second fast selector is the tag selector ($(` head )). The same is true because it comes from the native getElementsByTagName () method div id= content form method=, post, action= / h2Traffic Light/h2 ul id= traffic_light liinput type= radio class= on name= light value=