重写alert方法

<!DOCTYPE html>
<html lang="en">
<head>
	<meta charset="UTF-8">
	<title>重写alert方法</title>
	<style type="text/css">
		*{margin:0;padding:0;font-size:12px;}
		.m-alert{
			position: absolute;
			left: 0;
			right: 0;
			top: 0;
			bottom: 0;
			margin: auto;
			 200px;
			height: 100px;
		   	background: #ccc;
		    text-align: center;
		    border: 1px solid #999;
		}
		.u-con{
			height: 60px;
			line-height: 60px;
			color: #fff;
		}
		.u-btn{
			display: inline-block;
			cursor: pointer;
			 80px;
			height: 20px;
			line-height: 20px;
			background: #999;
			margin-top: 10px;
			border: 1px solid #FFF;
		}
	</style>
</head>
<body>
	
</body>
<script type="text/javascript">
window.alert = function(str){
    var alertWrap = document.createElement("div");
    var alertBtn =  document.createElement("a");
    var alertContent =  document.createElement("p");

    alertContent.innerHTML = str;
    alertBtn.innerHTML = "关闭";

    alertWrap.className = "m-alert";
    alertBtn.className = "u-btn";
    alertContent.className = "u-con";

    alertWrap.appendChild(alertContent);
    alertWrap.appendChild(alertBtn);
    document.body.appendChild(alertWrap);

}
alert('弹窗666');
</script>
</html>

  

原文地址:https://www.cnblogs.com/vleexy/p/6588559.html