<script type="text/javascript">
var CreateDiv = (function(){
var instance;
var CreateDiv = function(html){
if(instance){
return instance;
}
this.html = html;
this.init();
return instance = this;
};
CreateDiv.prototype.init = function() {
var div = document.createElement('div');
div.innerHTML = this.html;
document.body.appendChild(div);
};
return CreateDiv;
})();
var a = new CreateDiv('sven1');
var b = new CreateDiv('sven2');
alert(a === b);
</script>
此段代码报错,can not read property appendChild of null