function ShowCookie(cName){//展示cookie中的每个键值对
  var i;
  var value = document.cookie;
  var arr1 = value.split(";");
  var sCookie = ""; 
  for(i=0;i<arr1.length;i++){
  	try {
	    if(value.length == 0){
	      break;
	    }
	    sName =  strim(arr1[i].split("=")[0]);
	    sValue =  strim(arr1[i].split("=")[1]);
		if (sName == cName) {
			sCookie = sValue; 
		}
	} catch(e) {}
  }
  return sCookie;
}

function strim(sT)  
{  
  if(sT == null) {
   return "";
 }
  if(sT.length > 0){
   return  sT.replace(/(^\s*)|(\s*$)/g,  "");
  }
  else{
   return sT;
  }
}  

function setcookie(cname,cvalue,cdate)
{
   var expires = new Date();
   expires.setTime(expires.getTime() + cdate);
   document.cookie=cname + "=" + escape(cvalue) + ";path=/;expires=" + expires.toGMTString();
   //alert("设置了一个名为" + cname + "的cookie.值是:" + cvalue + "过期时间是:" + expires.toGMTString());
}