php中结合Ajax的有关问题

php中结合Ajax的问题
删除页：del.php

HTML code

<!--Code highlighting produced by Actipro CodeHighlighter (freeware)http://www.CodeHighlighter.com/-->   <title>Information</title>  <script type="text/javascript">    var xmlHttp ;    function createXMLHttpRequest(){        if(window.ActiveXObject){            xmlHttp=new ActiveXObject("Microsoft.XMLHTTP") ;        }else if(window.XMLHttpRequest){            xmlHttp=new XMLHttpRequest() ;        }    }    function show(){        createXMLHttpRequest() ;        var url="delsend.php" ;        xmlHttp.onreadystatechange=callback ;        xmlHttp.open("GET" , url , true) ;        xmlHttp.send(null) ;    }    function callback(){        if(xmlHttp.readyState==4){            if(xmlHttp.status==200){                chk() ;            }        }    }    function chk(){        var xmlDoc=xmlHttp.responseXML ;        var yan=xmlDoc.getElementsByTagName("content") ;        var ta="<table border='1' align='center'><th>用户编号<th>用户<th>聊天内容<th>聊天时间<th>操作" ;        for(var i=0 ; i<yan.length ; i++){            var y=yan[i] ;            ta+="<tr><td>"+y.childNodes[0].firstChild.data+"" ;            ta+="<td>"+y.childNodes[1].firstChild.data+"" ;            ta+="<td>"+y.childNodes[2].firstChild.data+"" ;            ta+="<td>"+y.childNodes[3].firstChild.data+"" ;            ta+="<td><span id="+y.childNodes[4].firstChild.data+" onclick='start(this)'>删除" ;        }        ta +="" ;        document.getElementById("del").innerHTML=ta ;        //alert(yan.length) ;    }    function start(ele){        var id=ele.id ;        createXMLHttpRequest() ;        var urldel="startsend.php?key="+escape(id) ;        xmlHttp.onreadystatechange=back ;        xmlHttp.open("GET" , urldel , true) ;        xmlHttp.send(null) ;    }    function back(){        if(xmlHttp.readyState==4){                if(xmlHttp.status==200){                    var str=xmlHttp.responseText ;                    if(str=="1"){                    alert("该项已被删除，1秒之后显示新的信息") ;                    setTimeout("show()" , 1000) ;                    }                }        }    }  </script>   <?php error_reporting(E_ALL & ~E_NOTICE); ?>  <div align="center">    <h2 id="删除信息">删除信息</h2>    <div id="del"></div>  </div> 

[/code]delsend.php

PHP code

<!--Code highlighting produced by Actipro CodeHighlighter (freeware)http://www.CodeHighlighter.com/--><?phpheader ("Content-Type:text/xml") ;header("cache-control:no-cache , must-revalidate") ;error_reporting(E_ALL & ~E_NOTICE);$xml="<?xml version='1.0' encoding='gb2312'?>" ;$xml=$xml."<contents>" ;include_once("conn.php") ;$result=mysql_query("select * from chatcontent") ;while($rs=mysql_fetch_object($result)){    $content.="<content><userid>".$rs->user_id."</userid><name>".$rs->name."</name><content1>".$rs->content."</content1><date>".$rs->showdate."</date><time>".$rs->id."</time></content>" ;}$xml=$xml.$content."</contents>" ;echo $xml ;mysql_close() ;?>

[/code]startsend.php

PHP code

<!--Code highlighting produced by Actipro CodeHighlighter (freeware)http://www.CodeHighlighter.com/--><?php error_reporting(E_ALL & ~E_NOTICE);    $id=$_GET["key"] ;    include_once("conn.php") ;    $result=mysql_query("delete from chatcontent where id='$id'") ;    if($result){        echo "1" ;        //echo "<script type='text/javascript'>window.location='del.php' ;" ;    }    mysql_close() ;?><div class="clear">
                 
              
              
        
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