function openWindow(){
       var world=confirm('请输入网址：');
       if(world==true){
           var home=prompt("http：//www.imooc.com/");
       if(home!==null){
           window.open(home,'_blank','width=400,height=500,toolbar=no,meunubar=no');}
          
       }
      
      
       else
       {document.write("下次再来")}