(function(){
......
})()
(function(){
// 声明一个 jQuery函数
function jQuery(){
}
// 给 window 对象添加一个 jQuery 函数
window.$ = window.jQuery = jQuery;
})()
- 实现功能：$("div").css("color", "red")
(function() {
function jQuery(selector) {
return new jQuery.prototype.init(selector);
}
window.$ = window.jQuery = jQuery;
jQuery.prototype = {
constructor:jQuery,
init:function(selector) {
var elements = document.querySelectorAll(selector);
for (var i=0; i<elements.length; i++) {
this[i] = elements[i];
}
this.length = elements.length;
}
}
jQuery.prototype.init.prototype = {
constructor:jQuery.prototype.init,
css:function(name, value) {
for (var i=0; i<this.length; i++) {
this[i].style[name] = value;
}
}
}
})()
<!DOCTYPE html>
<html lang="en">
<head>
<meta charset="UTF-8">
<meta name="viewport" content="width=device-width, initial-scale=1.0">
<meta http-equiv="X-UA-Compatible" content="ie=edge">
<title>Document</title>
</head>
<body>
<div>1</div>
<div>2</div>
<div>3</div>
<script>
(function() {
function jQuery(selector) {
return new jQuery.prototype.init(selector);
}
window.$ = window.jQuery = jQuery;
jQuery.prototype = {
constructor:jQuery,
init:function(selector) {
var elements = document.querySelectorAll(selector);
for (var i=0; i<elements.length; i++) {
this[i] = elements[i];
}
this.length = elements.length;
}
}
jQuery.prototype.init.prototype = {
constructor:jQuery.prototype.init,
css:function(name, value) {
for (var i=0; i<this.length; i++) {
this[i].style[name] = value;
}
}
}
})()
$("div").css('color', 'red');
</script>
</body>
</html>
