function document.onkeydown()  
    {
        if (event.keyCode == 13)  
          {
              var btn = document.getElementById("Header1_imgBtnLogin"); 
           
           if(event.srcElement == document.getElementById("txtPassword")||event.srcElement == document.getElementById("txtLoginName"))
            {
                btn = document.getElementById("Header1_imgBtnLogin");  
            }

            if (event.srcElement == document.getElementById("txtSearch"))
            {
                btn = document.getElementById("Header1_imgBtnSearch");
            }
            btn.focus();  
            //btn.click();  
          }   
    }

     

    
  


     $(document).ready(function(){ 
 
        colors();
       
    });
     
     
     //搜索黄页文本框得到焦点时
    function colors(){
        $("#txtSearch").bind("focus", function() {

        $("#txtSearch").css("color", "#000000");
        if ($("#txtSearch").val() == "请输入关键字：例如机床")
            $("#txtSearch").val("");
     })

     $("#txtSearch").bind("blur", function() {

     $("#txtSearch").css("color", "#000000");
     if ($("#txtSearch").val() == "")
         $("#txtSearch").val("请输入关键字：例如机床");
     $("#txtSearch").css("color", "#CCCCCC");
        
     })
    };