想学好面向对象：熟悉this指向很重要！！！下面用几个简单的例子来复习this指向
<!DOCTYPE HTML>
<html>
<head>
<meta http-equiv="Content-Type" content="text/html; charset=utf-8">
<title>无标题文档</title>
<script>
oDiv.onclick = function(){
this : oDiv
};
oDiv.onclick = show;
function show(){
this : oDiv
}
oDiv.onclick = function(){
show();
};
function show(){
this : window
}
</script>
</head>
<body>
</body>
</html>