Ajax与PHP【1.4代码】

js代码：

var xmlHttp=createXmlHttpRequestObject();
//get xmlHttpRequest object
function createXmlHttpRequestObject(){
var xmlHttp;
if(window.ActiveXObject){
try{
xmlHttp=new ActiveXObject("Microsoft.XMLHTTP");
}
catch(e){
xmlHttp=false;
}
}else{
try{
xmlHttp=new XMLHttpRequest();

}
catch(e){
xmlHttp=false;
}

}
if(!xmlHttp){
}else{
return xmlHttp;
}
}

function process(){
if(xmlHttp.readyState==4||xmlHttp.readyState==0){
name=document.getElementById("myName").value;

xmlHttp.open("GET","quickstart.php?name="+name,true);
xmlHttp.onreadystatechange=handleServerResponse;
xmlHttp.send(null);

}else{
setTimeout('process()',1000);
}
}

function handleServerResponse(){
if(xmlHttp.readyState==4){
if(xmlHttp.status==200){
xmlResponse=xmlHttp.responseXML;
xmlDocumentElement=xmlResponse.documentElement;
helloMessage=xmlDocumentElement.firstChild.data;
document.getElementById('divMessage').innerHTML='<i>'+helloMessage+'</i>';
setTimeout('process()',1000);

}else{
alert('There was a problem accessing hte server:'+xmlHttp.statusText);
}
}
}

php代码：

遇到了 一个

<pre name="code" class="plain">Warning: Cannot modify header information - headers already sent by....

解决方法：

修改php.ini文件，

我用的是阿里的服务器所以

启用如下如的功能就可以了。

<img src="http://img.blog.csdn.net/20160319103516024?watermark/2/text/aHR0cDovL2Jsb2cuY3Nkbi5uZXQv/font/5a6L5L2T/fontsize/400/fill/I0JBQkFCMA==/dissolve/70/gravity/Center" alt="" />

<pre name="code" class="php"><?php
header('Content-Type:text/xml');
echo '<?xml version="1.0" encoding="UTF-8" standalone="yes"?>';
echo'<response>';
$name=$_GET['name'];
$userNames=array('WangWei','ZhouJianfei','MeiShibo','QuXinglin','WangYuming','LiaoGuihong','WangChenggao','ZhouQian');
if(in_array($name,$userNames)){
echo'Hello,master'.htmlentities($name).'!';
}else if(trim($name)==''){
echo'Stranger,please tell me your name!';
}else{
echo htmlentities($name).',I don\'t know you!';
}
echo'</response>';
?>

<pre name="code" class="php">方法简介：

in_array($name,$userNames)：遍历uername数组中的元素，并每次赋值给name

strtoupper($str);将该str转换为大写。

<pre name="code" class="php">htmlentities($name):替换代码中不同字符的编码（eg：&，>等）,以防止出错。