Question

我正在参加AJAX课程。我一直在我的闪存驱动器上使用XAMPP便携式服务器测试以下文件，它们在本地工作没有问题。当我将它们发布到我的班级服务器时，它们无法工作，我在Chrome控制台中收到错误：“未捕获的类型错误无法调用方法'getelementsbytagname'为null”（请参阅下面代码注释中的内容）。

为什么这些文件可以在本地运行但不能生效？页面的用途是输入文本以从XML文件中查找客户名称，然后根据输入的字母使用XML文件中的值填充表格。如果键入的文本被删除，则表格会相应更新，如果不存在文本，那就没有桌子了。

HTML：

<html>

<head>

<script>

    function addToTable()
    {
        var input = document.getElementById("input");
        var XMLHttpRequestObject = false;

        if (window.XMLHttpRequest)
        {
        XMLHttpRequestObject = new XMLHttpRequest();
            if (XMLHttpRequestObject.overrideMimeType)
            {
                XMLHttpRequestObject.overrideMimeType("text/xml");
            }
        }
        else if (window.ActiveXObject)
        {
            XMLHttpRequestObject = new ActiveXObject("Microsoft.XMLHTTP");
        }
        if(XMLHttpRequestObject)
        {
            XMLHttpRequestObject.open("GET", "hw8a.php?sid=" + Math.random() + "&qu=" + input.value);
            XMLHttpRequestObject.onreadystatechange =
            function()
            {
                if (XMLHttpRequestObject.readyState == 4 && XMLHttpRequestObject.status == 200)


                {
                    xmlDocument = XMLHttpRequestObject.responseXML;
                    if (xmlDocument.getElementsByTagName("Data").length == 0)

// ERROR APPEARS HERE: "uncaught typeerror cannot call method 'getelementsbytagname' of null"
                    {
                        not_there();
                    }
                    else
                    {
                        there(xmlDocument);
                    }
                }
            }
            XMLHttpRequestObject.send(null);
        }
    }

    function there(documentElement)
    {
        if (input != "")
        {
            not_there();

            var nodeNames =  new Array("CustomerID", "FirstName", "LastName", "Address", "ZipCode", "Phone");

            var result = document.getElementById("result");

            customerCount = documentElement.getElementsByTagName("Customer").length;

            for(var i = 0; i < customerCount; i++)
            {
                var newRow = result.insertRow(i+1);
                customerNode = documentElement.getElementsByTagName("Customer")[i];

                for (var j = 0; j < nodeNames.length; j++)
                {
                    var col = newRow.insertCell(j);
                    col.innerHTML = customerNode.getElementsByTagName(nodeNames[j])[0].firstChild.nodeValue;
                }
            }
        }
    }

    function not_there()
    {
        var result = document.getElementById("result");

        while(result.rows.length > 1)
        {
        result.deleteRow(1);
        }
    }

</script>

</head>

<body>

<h1 align="center">Choose Customer Information from the Database</h1>

<p align="center">Enter the last name of a customer here: <input id="input" type="text" onkeyup="addToTable();" /> and a table of customer data will appear below...</p>

<table align="center" cellspacing="5" id="result">

<tr><th>ID</th><th colspan="2">Name</th><th>Address</th><th>Zip</th><th>Phone</th></tr>

<tr><td></td><td></td><td></td><td></td><td></td><td></td></tr>

</table>

</body>

</html>

PHP：

<?php

include "XMLParser.class";

header("Cache-Control: post-check=1,pre-check=2");

header("Cache-Control: no-cache, must-revalidate");

header("Pragma: no-cache");

header("Content-type: text/xml");

echo '<?xml version="1.0"?>';

echo '<Data>';

$xml = file_get_contents('Customer.xml');

$parser = new XMLParser($xml);

$parser->Parse();

$input = $_GET["qu"];

$found = false;

foreach( $parser->document->customer as $customer)
{
    if ($input == "")
    {
        echo "not_there()";
    }
    else if (stripos($customer->lastname[0]->tagData, $input) === 0) 
    {
        $found = true;
        echo '<Customer>';
        echo '<CustomerID>' . $customer->customerid[0]->tagData . '</CustomerID>';
        echo '<FirstName>' . $customer->firstname[0]->tagData . '</FirstName>';
        echo '<LastName>' . $customer->lastname[0]->tagData . '</LastName>';
        echo '<Address>' . $customer->address[0]->tagData . '</Address>';
        echo '<ZipCode>' . $customer->zipcode[0]->tagData . '</ZipCode>';
        echo '<Phone>' . $customer->phone[0]->tagData . '</Phone>';
        echo '</Customer>';
    }
}

echo '</Data>';

?>

XML示例：

<?xml version="1.0" encoding="UTF-8"?>
<Data>
    <Customer>
        <CustomerID>2</CustomerID>
        <Phone>(999) 555-1111</Phone>
        <FirstName>Something</FirstName>
        <LastName>Something</LastName>
        <Address>1234 Something Street</Address>
        <ZipCode>99999</ZipCode>
    </Customer>
        . . .
</Data>

PHP可以在本地使用XAMPP，但不能在线“实时”使用

0 个答案: