Question

我正在通过遵循newboston的教程学习如何使用AJAX。我一直收到xmlHttpRequest状态为0而不是200.我已查询状态0是什么，并且表明我的请求未初始化。我一直在研究我的文件，但我无法弄清楚它为什么会这样做。

我相信我把它缩小到xmlHttp.open不正确＆＃34;链接＆＃34;？到我的foodstore.php文件，或者foodstore.php文件中有错误写入的内容。

我的文件都存储在htdocs文件夹中，Apache Web Server在XAMMP 1.8.3-4上本地运行。

的index.html

<!DOCTYPE html>
<html>
    <head>
        <script type="text/javascript" src="foodstore.js"></script>
    </head>
    <body onload="process()">
        <h3>The Chuff Bucket</h3>
        Enter the food you would like to order:
        <input type="text" id="userInput" />
        <div id="underInput" />
    </body>
</html>

foodstore.js

var xmlHttp = createXmlHttpRequestObject();

//creates connection 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)
        alert("cant create that object boss!");
    else
        return xmlHttp;
}

//processes object
function process(){
    if(xmlHttp.readyState == 0 || xmlHttp.readyState == 4){
        alert('process run!');
        var food = encodeURIComponent(document.getElementById("userInput").value);
        xmlHttp.open("GET", "foodstore.php?food="+food, true);
        xmlHttp.onreadystatechange = handleServerResponse; 
        xmlHttp.send(null);
    }else{
        alert('process NOT run!');
        setTimeout('process()',1000);
    }
}

function handleServerResponse(){
    if(xmlHttp.readyState == 4){
        //check if communication session is OK. no errors 
        alert('xmlHttp status: ' + xmlHttp.status);
        if(xmlHttp.status == 200){
            xmlResponse = xmlHttp.responseXML;
            xmlDocumentElement = xmlResponse.documentElement; 
            message = xmlDocumentElement.firstChild.data; //message equals data between response tags from foodstore.php
            document.getElementById("underInput").innerHTML = '<span style="color:blue">' + message + '</span>';
            setTimeout('process()', 1000);
        }else{
            alert('Something went wrong!');
        }
    }
}

foodstore.php

<?php
header('Content-Type: text/xml');
echo '<?xml version="1.0" encoding="UTF-8" standalone="yes" ?>';

echo '<response>';
    $food = $_GET['food'];
    $foodArray = array('tuna','ham','bacon','chicken');

    if(in_array($food, $foodArray))
        echo 'We do have ' . $food . '!';
    elseif($food == '')
        echo 'Enter a food';
    else
        echo 'Sorry we dont sell ' . $food . '!';
echo '</response>';
?>

XMLHttpRequest状态为0而不是200

0 个答案: