IE浏览器出现 SCRIPT5007: Unable to get property 'getElementsByTagName' of undefined or null referenc

比眉伴天荒 2022-02-24 11:36 101阅读 0赞

这个问题是在写ajax时出现的，在不同的浏览器中具体的错误会有不同，但实际上不是这个函数和方法的问题。

var number = xmlDoc.getElementsByTagName("number")[0].childNodes[0].nodeValue;

这个函数本身是没有问题的。后来经过检查有问题的是我的php文件：

<?php
    
    $servername ="localhost";
    $username = "root";
    $password = "123456";
    // 创建连接
    $conn = mysqli_connect($servername, $username, $password);
    // 检测连接
    if (!$conn) {
        die("Connection failed: " . mysqli_connect_error());
    }
    $res=mysqli_select_db($conn,"test");
    if ($res==0)
    echo "选择数据库出错";
    
    //$ttt="'".$_GET['values']."'";
    $tt="SELECT * FROM friendship WHERE userId='1'";
    $number=0;
    //$sql = "SELECT content FROM blog where lookNum=43";
    $result1=mysqli_query($conn,$tt);
    
    if($result1==0)
     {
      printf("Error: %s\n", mysqli_error($conn));
      exit();
    }
    echo '<?xml version="1.0" encoding="ISO-8859-1"?><person>';
    while($row=mysqli_fetch_array($result1))
    {
        
        echo "<friendld>".$row['friendId']."</friendld>";
       // echo "<time>".$row['time']."</time>";
        //echo "<br>";
        $number++;
        //echo "<br>";
        //header("location:url地址");
    }
    echo "<number>".$number."</number>";
    echo '</person>';
      ?>

我单独运行这个php文件时的结果：

![2019040322192757.png][]

发现这结果明显不对，后来对比了一下我原来的代码发现少了关键的两行（在php头部加入）：

header('Content-Type: text/xml');
    header("Cache-Control: no-cache, must-revalidate");

完整的php文件：

<?php
     //一定要加，因为没加导致错误
    header('Content-Type: text/xml');
    header("Cache-Control: no-cache, must-revalidate");
    $servername ="localhost";
    $username = "root";
    $password = "123456";
    // 创建连接
    $conn = mysqli_connect($servername, $username, $password);
    // 检测连接
    if (!$conn) {
        die("Connection failed: " . mysqli_connect_error());
    }
    $res=mysqli_select_db($conn,"test");
    if ($res==0)
    echo "选择数据库出错";
    
    //$ttt="'".$_GET['values']."'";
    $tt="SELECT * FROM friendship WHERE userId='1'";
    $number=0;
    //$sql = "SELECT content FROM blog where lookNum=43";
    $result1=mysqli_query($conn,$tt);
    
    if($result1==0)
     {
      printf("Error: %s\n", mysqli_error($conn));
      exit();
    }
    echo '<?xml version="1.0" encoding="ISO-8859-1"?><person>';
    while($row=mysqli_fetch_array($result1))
    {
        
        echo "<friendld>".$row['friendId']."</friendld>";
       // echo "<time>".$row['time']."</time>";
        //echo "<br>";
        $number++;
        //echo "<br>";
        //header("location:url地址");
    }
    echo "<number>".$number."</number>";
    echo '</person>';
      ?>

现在的效果：

![watermark_type_ZmFuZ3poZW5naGVpdGk_shadow_10_text_aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L3FxXzM4MjQ3NTQ0_size_16_color_FFFFFF_t_70][]

这样就好了：

这两句的具体意思可参考：[https://www.cnblogs.com/dhsx/p/4827926.html][https_www.cnblogs.com_dhsx_p_4827926.html]

[2019040322192757.png]: /images/20220224/d4c75d177f9d4aa3910162232f09688f.png
[watermark_type_ZmFuZ3poZW5naGVpdGk_shadow_10_text_aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L3FxXzM4MjQ3NTQ0_size_16_color_FFFFFF_t_70]: /images/20220224/ae883c45028a43a18e09b8f9dbe81f8d.png
[https_www.cnblogs.com_dhsx_p_4827926.html]: https://www.cnblogs.com/dhsx/p/4827926.html