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HomeBackend DevelopmentPHP Tutorial一直揭示:xmlhttp is not defined

一直提示:xmlhttp is not defined
描述:在做一个公共聊天室的页面,在用户提交发言后,在公共讨论区显示发言。
talk.php文件中的提交代码:
 


其中还包含了:
 
 
js函数tk就是在main.js中定义的,代码为:
  function tk(form,maxtm){
if(form.cont.value==""){
alert("发言不允许为空!");
form.cont.focus();
return false
}
face = form.face.value;
color = form.color.value;
obt = form.obt.value;
cont = form.cont.value;
var url = "talk_chk.php?action=send&face="+face+"&color="+color+"&obt="+obt+"&cont="+cont;
xmlhttp.open("Get",url,true);
xmlhttp.onreadystatechange = callback;
xmlhttp.send(null);
form.cont.value="";
form.cont.focus();
refrsh(maxtm);
return false;
}
但是提交发言后,提示: xmlhttp is not defined !! 弄了一晚上了,跪求!!!!!!
xmlhttprequest.js中的代码:
  if(window.ActiveXObject){
xmlhttp = new ActiveXObject("Microsoft.XMLHTTP");
}else if(window.XMLHttpReuqest){
xmlhttp = new XMLHttpRequest();
}

------解决方案--------------------
else if( window.XMLHttpReuqest )
这里错了, 是 XMLHttpRequest

所以这才导致没有进入任何一个分支,自然xmlhttp未定义
------解决方案--------------------
IE下的有几个不同版本 找齐咯
------解决方案--------------------
别用原生的xmlhttp,用类库吧,jquery,mootools皆可
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