html头添加代码
<meta http-equiv="refresh" content="3; url=http://www.baidu.com/" />
js实现
一、最外层top跳转页面,适合用于iframe框架集
top.window.location.href("http://www.baidu.com");
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二、window.location.href和window.location.replace的区别
1.window.location.href=“url”:改变url地址;
   2.window.location.replace(“url”):将地址替换成新url,该方法通过指定URL替换当前缓存在历史里(客户端)的项目,
	  因此当使用replace方法之后,你不能通过“前进”和“后 退”来访问已经被替换的URL,这个特点对于做一些过渡页面非常有用!
三、强制页面刷新
1.window.location.reload():强制刷新页面,从服务器重新请求!
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四、window.location.reload();
页面实现跳转和刷新:
	  1 history.go(0)
	  2 location.reload()
	  3 location=location
	  4 location.assign(location)
	  5 document.execCommand('Refresh')
	  6 window.navigate(location)
	  7 location.replace(location)
	  8 document.URL=location.href
这几个都可以刷新:
	  window.location.reload();刷新
	  window.location.href=window.location.href;刷新
	  window.close();关闭窗口,不弹出系统提示,直接关闭 
	  window.close()相当于self属性是当前窗口
	  window.parent.close()是parent属性是当前窗口或框架的框架组
页面实现跳转的九种方法实例:
1 setTimeout('window.navigate("top.html");',2000);
2 setTimeout('window.document.location.href="top.html";',2000);
3 setTimeout('window.document.location="top.html";',2000);
4 setTimeout('window.location.href="top.html";',2000);
5 setTimeout('window.location="top.html";',2000);
6 setTimeout('document.location.href="top.html";',2000); 
7 setTimeout('document.location="top.html";',2000);
8 setTimeout('location.href="top.html";',2000);
9 setTimeout('location.replace("top.html")',2000);
//window对象
   //document对象
	  //location对象
	  //href属性
	  //1.window.document.location.href
	  //2.window.document.location
	  //3.window.location.href
	  //4.window.location
	  //5.document.location.href
	  //6.document.location
	  //7.location.href
	  //8.window.navigate
	  //9.location.replace
只要使用location方法,和任意的window对象,location对象,href属性连用,都可以页面的跳转
解释:
  location是个对象,比如本页的document.location和window.location的属性有    
	  location.hostname   =   community.csdn.net 
	  location.href   =   http://community.csdn.net/Expert/topic/4033/4033372.xml?temp=2.695864E-02 
	  location.host   =   community.csdn.net 
	  location.hash   =   
	  location.port   =   
	  location.pathname   =   /Expert/topic/4033/4033372.xml 
	  location.search   =   ?temp=2.695864E-02 
	  location.protocol   =   http: 
	可见href是location的属性,类别是string。
来源:https://www.cnblogs.com/mrxia/p/3573615.html