for循环简单应用(1)

<!DOCTYPE HTML>
<html>
<head>
<meta http-equiv="Content-Type" content="text/html; charset=utf-8">
<title>无标题文档</title>

<script>
window.onload = function (){

// +=
/*
document.body.innerHTML += '<input type="button" value="按钮" />';
document.body.innerHTML += '<input type="button" value="按钮" />';
document.body.innerHTML += '<input type="button" value="按钮" />';
*/

// 性能有问题!!!

var str = '';
for( var i=0; i<6000; i++ ){
// document.body.innerHTML += '<input type="button" value="按钮" />';
str += '<input type="button" value="按钮" />';
}

document.body.innerHTML = str;
};
</script>

</head>

<body>
</body>
</html>

原文地址:https://www.cnblogs.com/zhousha929-/p/6907562.html