Question

我搜索过并偶然发现了许多像这样的问题。但这没有回答我的问题。因此，我在这里再问一次。这是我的PHP代码：

<?php
    include("connect.php");
    if(isset($_GET['view'])) {
        $query = "SELECT * FROM posts order by 1 DESC";
        $run = mysqli_query($con, $query);

        while(mysqli_fetch_array($run)) {
        $id = $row['Post_id'];
        $title = $row['Post_title'];
        $date = $row['Post_date'];
        $author = $row['Post_author'];
        $content = $row['Post_content'];
?>
    <table width="800" align="center" border="5">
            <tr>
                   <td align="center" colspan="9"><h1>View all Posts</h1></td>
            </tr>
                </table>
   <?php
        } 
   } 
   ?>

问题在于最后一行<?php } } ?>我所关注的教师正是这样做的。他的代码工作得非常好。但我的错误是“第27,28,29,30行的未定义变量行”。任何帮助将不胜感激。

Answer 1

您需要在while循环中定义$row以迭代查询中的每条记录：

while($row = mysqli_fetch_array($run)) {
    // Do something
}

Answer 2

您应该定义$row变量。

<?php
    include("connect.php");
        if(isset($_GET['view'])) {
            $query = "SELECT * FROM posts order by 1 DESC";
            $run = mysqli_query($con, $query);

            while($row = mysqli_fetch_array($run)) {
            $id = $row['Post_id'];
            $title = $row['Post_title'];
            $date = $row['Post_date'];
            $author = $row['Post_author'];
            $content = $row['Post_content'];
        ?>

    <table width="800" align="center" border="5">
            <tr>
                   <td align="center" colspan="9"><h1>View all Posts</h1></td>
            </tr>
                </table>
                            <?php } } ?>

Answer 3

只需改变

 while($row = mysqli_fetch_array($run)) {

//Code
}

Answer 4

试试这个

<?php
    include("connect.php");
    if(isset($_GET['view'])) {
        $query = "SELECT * FROM posts order by 1 DESC";
        $run = mysqli_query($con, $query);

        while($row =mysqli_fetch_array($run)) {
        $id = $row['Post_id'];
        $title = $row['Post_title'];
        $date = $row['Post_date'];
        $author = $row['Post_author'];
        $content = $row['Post_content'];
?>
    <table width="800" align="center" border="5">
            <tr>
                   <td align="center" colspan="9"><h1>View all Posts</h1></td>
            </tr>
                </table>
   <?php
        } 
   } 
   ?>

Answer 5

是。因为你没有定义数组$ row。你必须定义 $ row = array（）;在使用它之前。如下所示

<?php
    include("connect.php");
        if(isset($_GET['view'])) {
            $query = "SELECT * FROM posts order by 1 DESC";
            $run = mysqli_query($con, $query);
             $row= array();
            while($row = mysqli_fetch_array($run)) {
            $id = $row['Post_id'];
            $title = $row['Post_title'];
            $date = $row['Post_date'];
            $author = $row['Post_author'];
            $content = $row['Post_content'];
        ?>
<table width="800" align="center" border="5">
            <tr>
                   <td align="center" colspan="9"><h1>View all Posts</h1></td>
            </tr>
                </table>
                            <?php } } ?>

这应该适合你。

Answer 6

定义$ row变量。

while($row=mysqli_fetch_array($run))

在关闭标记之外关闭while循环并使用Html时出现PHP错误

6 个答案: