function CrossDomainName(target, agent, callback, security) {
	if (typeof target !== 'string' || typeof agent !== 'string' || typeof callback !== 'function') {
		throw '参数错误';
	}
	this.state = 0;
	this.target = target;
	this.agent = agent;
	this.callback = callback || Function;
	this.security = security || true;
	this.iframe = document.createElement('iframe');
	var self = this;
	function onload() {
		if (self.state === 1) {
			var data = self.iframe.contentWindow.name;
			self.callback.call(self.iframe, data);
			if (self) {
				self.iframe.contentWindow.document.close();//关闭文档流
				self.iframe.contentWindow.close();//关闭Iframe
				document.body.removeChild(self.iframe);//移除Iframe
			}
		} else if (self.state === 0) {
			self.state = 1;
			self.iframe.contentWindow.location = self.agent;
		}
	}
	if (document.attachEvent) {
		this.iframe.attachEvent('onload', onload);
	} else if (document.addEventListener) {
		this.iframe.addEventListener('load', onload, false);
	} else {
		this.iframe.onload = onload;
	}
	this.iframe.src = this.target;
	document.body.appendChild(this.iframe);
}
//调用
new CrossDomainName('http://www.kingwell.com/kingwell.html', 'http://name.b.com/adfas.html', function (data) {
	alert(data);
});

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