// 从DB中读取文件并且显示的函数:
function readData(){
	var xmlhttp=initxmlhttp();
	var class_id=document.getElementById("game_id").value;
	document.plform.pl_price.value="";
	document.plform.need_time.value="";
	var url='operation.php?action=read&class_id='+class_id;
	xmlhttp.open('GET',url,true);
	xmlhttp.onreadystatechange=function(){
		if(xmlhttp.readyState==4 && (xmlhttp.status==200 || xmlhttp.status == 304))
			{
				//alert(class_id);
				var change_getpricedy=document.getElementById("showlv_price");
				change_getpricedy.innerHTML=xmlhttp.responseText;				
				var change_img=document.getElementById("subimg");
				change_img.style.display = 'None';	
				//discontinue.style.display = 'block';
			}
	}
	xmlhttp.send(null);		
}