function Ajax(data) { createXMLHttpRequest(); if(data==document.getElementById("username")) { xmlhttp.open("GET","user_ck.php?username="+data.value,true); document.getElementById('username_notice').innerHTML = process_request;//显示状态 } else if(data==document.getElementById("veruserid")) { xmlhttp.open("GET","user_ck.php?veruserid="+data.value,true); document.getElementById("veruserid_notice").innerHTML = process_request;//显示状态 } else if (data==document.getElementById("verify")) { xmlhttp.open("POST","veruser_check.php",true); xmlhttp.setRequestHeader('Content-Type', 'application/x-www-form-urlencoded'); document.getElementById("verify_notice").innerHTML = process_request;//显示状态 }//"checkcode="+checkcode.value+"&username="+ xmlhttp.onreadystatechange=function() { //alert("zhong"); if (4==xmlhttp.readyState) { if (200==xmlhttp.status) { var responseText = xmlhttp.responseText; responseText= responseText.replace(/(^\s*)|(\s*$)/g,""); if (responseText=="true" ) { ck_user(data,"true"); } else { ck_user(data,"false"); } } else { alert("发生错误!"); } } } if(data==document.getElementById("veruserid")||data==document.getElementById("username")) { xmlhttp.setRequestHeader("If-Modified-Since","0"); xmlhttp.send(null); } else if (data==document.getElementById("verify")) { xmlhttp.send("veruserid="+document.getElementById("veruserid").value+"&veruserpwd="+document.getElementById("verpassword").value); } }