最佳实践

  function popUp(winURL){
   window.open(winURL,"popup","width=320,height=480");//打开一个名字为popup,地址为winURL，长480px，宽320px的页面。
}

  <a herf="http://www.example.com/"return:false>Example</a>  //当点击标签时不会跳转到herf指定的页面，return：false；
  <a herf="http://www.example.com/" onclick="popup(this.getAttribute("herf");return false;)">Example</a> // 执行点击事件。

  window.onload=function(){                             //当打开页面时运行相应的程序
    if(!document.getElementBytagName) return false;
    var lnks=document.getElementByTagName("a");
    for(var i=0;i<lnks.length;i++){
       
  }  
}

   function parperGallery(){
     if(!documengt.getElementBTagName) return false;
     if(!document.getElementById) return false;
     if(!document.getElementById("imagegallery")) return false;
     var gallery =document.getElementById("imageallery")
     var links = gallery.getElementByTagName("a");
     for(var i=0; i<links.length;iu++){
       links[i].onclick =function(){
         return showpic(this) ? false:ture; 
     } 
  }
}
function showpic(whichpic){
   if(!document.getElementById("place")) return false;
   var source=whichpic.getAttribute("herf")
   var place=document.getElementById("place")
   place.setAttribute("src",source)
   if(document.getElementById("description")){
    var text=whichpic.getAttribute("title")
    var description=document.getElementById("description")
    description.firstChild.nodevalue =text;    
   }
  return ture;
}