var l = 0;
var downid =0;
var count = 4;
var dl =0;

function showDoc()
{
    var divs   =   document.getElementsByTagName("DIV");   
    var div_up =  document.getElementById("div_up");
    var div_up_stop =  document.getElementById("div_up_stop");
    var div_down =  document.getElementById("div_down");
    var div_down_stop =  document.getElementById("div_down_stop");
   
    l = divs.length;
    for(var   i   =   0;i < l; i++)  
      {     
          
          if(divs[i].id.indexOf("pr_") ==0)
          {        
            document.getElementById(divs[i].id).style.display='none';
            dl = dl+1;
          }
          
      }
      
      if(dl <= 4)
      {
            count = dl; 
            div_down.style.display="none";
            div_down_stop.style.display="block";
      }
      else
      {
          div_down.style.display="block";
          div_down_stop.style.display="none";
      }
      for(var k = 0; k < count ; k++)
      {
          document.getElementById("pr_"+k).style.display='block';
      }
     
      div_up.style.display="none";
      div_up_stop.style.display="block";
}
//向下
function down()
{
    var div_up =  document.getElementById("div_up");
    var div_up_stop =  document.getElementById("div_up_stop");
    var div_down =  document.getElementById("div_down");
    var div_down_stop =  document.getElementById("div_down_stop");
    var   divs   =   document.getElementsByTagName("DIV");   
    l = divs.length;  
    for(var   i   =   0;i<l;i++)  
      {      
          if(divs[i].id.indexOf("pr_") ==0)
          {        
            document.getElementById(divs[i].id).style.display='none';
          }        
      } 
    downid = downid + 1 ;
    if(dl <= 4 )
    {
       count = dl;
       div_down.style.display="none";
       div_down_stop.style.display="block";
    }
    
    if((downid + 4) >= dl)
    {
        count = dl;
        div_down.style.display="none";
        div_down_stop.style.display="block";
    }
    else
        count=downid+4;
    for(var k = downid; k <count ; k++)
      {
          document.getElementById("pr_"+k).style.display='block';  
      }
    div_up.style.display="block";
    div_up_stop.style.display="none";
}

//向上
function up()
{
    var div_up =  document.getElementById("div_up");
    var div_up_stop =  document.getElementById("div_up_stop");
    var div_down =  document.getElementById("div_down");
    var div_down_stop =  document.getElementById("div_down_stop");
    var   divs   =   document.getElementsByTagName("DIV");   
    l = divs.length;  
    for(var   i   =   0;i<l;i++)  
      {      
          if(divs[i].id.indexOf("pr_") ==0)
          {        
            document.getElementById(divs[i].id).style.display='none';
          }        
      } 

    downid = downid - 1 ;
    if(downid <=0)
    {
        downid = 0;
        div_up.style.display="none";
        div_up_stop.style.display="block";
    }
    if(dl <= 4)
    {
        count = dl;
    }
    if((downid + 4) >= dl)
    {
        count = dl;
        div_down.style.display="none";
        div_down_stop.style.display="block";
    }
    else
        count = downid+4;
    for(var k = downid; k <count ; k++)
      {
          document.getElementById("pr_"+k).style.display='block';  
      }
      div_down.style.display="block";
      div_down_stop.style.display="none";
}


 var xmlHttp
function showImg(divID,str)
{
    xmlHttp =GetXMLHttpRequest();
    var url="/NormalImg.aspx?PictureProductID="+str; 
    xmlHttp.onreadystatechange = function() {GetImgSrc(divID)};
    xmlHttp.open('get',url,true);
    xmlHttp.send(null)
}

function GetImgSrc(divID)
{
 if(xmlHttp.readyState == 4)
     {
        if(xmlHttp.status == 200)
        { 
   
          var rntStr=  xmlHttp.responseText;
          var imglist =  rntStr.split("^");
        var img =  document.getElementById("caribbean");
      img.src=imglist[1];

         var div= document.getElementById(divID);
      div.style.backgroundImage= "url("+imglist[0]+")";  
        }
     }

}



function   GetXMLHttpRequest(url)
   {  
  
        if   (window.XMLHttpRequest)  
        {   
                objxml   =   new   XMLHttpRequest();   
               
        }  
         else   if   (window.ActiveXObject)  
        {   
                objxml   =   new   ActiveXObject("Msxml2.XMLHTTP");   
        }   
       
       return objxml;
}  

  
function   openUrl(url)
   {  
  
        if   (window.XMLHttpRequest)  
        {   
                objxml   =   new   XMLHttpRequest();   
               
        }  
         else   if   (window.ActiveXObject)  
        {   
                objxml   =   new   ActiveXObject("Msxml2.XMLHTTP");   
        }   
       
        objxml.open("GET",url,false);
      
        objxml.send(""); 
        retInfo=objxml.responseText;    
        
        if   (objxml.status== "200 ")
        {  
                return   retInfo;  
        }  
        else
        {  
                return   "";  
        }  
}