简单示例AJAX结合PHP代码实现登录效果代码

HTML部分：

functionpostRequest(strURL){
varxmlHttp;
if(window.XMLHttpRequest){//ForMozilla,Safari,...
varxmlHttp=newXMLHttpRequest();
}
elseif(window.ActiveXObject){//ForInternetExplorer
varxmlHttp=newActiveXObject("Microsoft.XMLHTTP");
}
xmlHttp.open('POST',strURL,true);
xmlHttp.setRequestHeader('Content-Type','application/x-www-form-urlencoded');
xmlHttp.onreadystatechange=function(){
if(xmlHttp.readyState==4){
updatepage(xmlHttp.responseText);
}
}
xmlHttp.send(strURL);
} functionupdatepage(str){
if(str=="yes"){
alert("WelcomeUser");
}else{
alert("InvalidLogin!Pleasetryagain!");
}
} functioncall_login(){
varusername=window.document.f1.username.value;
varpassword=window.document.f1.password.value;
varurl="login.PHP?username="+username+"&password="+password;
postRequest(url);
}


dalign="left"colspan="2">dalign="right"width="124">Name:dalign="right"width="124">ōnClick="call_login()">

PHP脚本部分login.PHP：

$username=$_GET["username"];
$password=$_GET["password"];
if($username=="admin"&&$password=="admin"){
echo"yes";
}else{
echo"No";
}
?>