在线运行代码 - 菜鸟教程

<!DOCTYPE html>
<html>
<head>
<meta charset="utf-8">
<title>菜鸟教程(cainiaoplay.com)</title>
</head>
<body>

<p id="demo">单击按钮，如果boolean值为<em>true</em>显示“green”,否则显示“red”。</p>
<button onclick="myFunction()">点我</button>
<script>
Boolean.prototype.myColor=function(){
	if (this.valueOf()==true){
		this.color="green";
	}
	else{
		this.color="red";
	}
}	
function myFunction(){
	var a = new Boolean(1);
	a.myColor();
	var x=document.getElementById("demo");
	x.innerHTML=a.color;
}
</script>

</body>
</html>
源代码

动行结果
