php - 在PHP中为外部函数定义$ id

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“Notice: Undefined variable”, “Notice: Undefined index”, and “Notice: Undefined offset” using PHP
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Reference: What is variable scope, which variables are accessible from where and what are “undefined variable” errors?
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去年关门了。
我正试图将玩家列表到一个页面中，该页面已经使用了一个sql查询，所以我将这个查询放在了functions.php中的一个函数（下面）中，在另一个文件teampage.php中，我调用了函数 <?php echo listGoalkeepersForTeam(); ?>，但它抛出了一个 Notice: Undefined variable: id in C:\xampp\***\functions.php on line 77
如何让函数读取teampage.php？id=1并相应地显示信息。

function listGoalkeepersForTeam() {

    $dbServername = "****";
    $dbUserrname = "****";
    $dbPassword = "****";
    $dbName = "****";

    $sql  = "select player.fname as fname, player.sname as sname, player.position as position, player.profile_img as profile_img from player_team 
    join player on player_team.player_id = player.player_id 
    join team on player_team.team_id = team.team_id 
    where team.team_id = '$id'
    AND player.position = 'Goalkeeper'";


    $conn = mysqli_connect($dbServername, $dbUserrname, $dbPassword, $dbName);
    $query = mysqli_query($conn, $sql);

    if (!$query) {
        die ('SQL Error: ' . mysqli_error($conn));
    }
    ?>
       <?php
       $no  = 1;
       $total   = 0;
       while ($row = mysqli_fetch_array($query))
       { ?>

                <img class="rounded-circle img-fluid d-block mx-auto mr-4" src="img/db_img/players/child.png" alt="<?php echo ($row['fname']. " " .$row['sname']) ?>">
                <h3><?php echo ($row['fname']. " " .$row['sname']) ?><br>
                <small><?php echo ($row['position']) ?></small>
                </h3>


<?php      $no++;
       } 

}

最佳答案

您没有从GET variable获取id。

function listGoalkeepersForTeam() {
//insert line
$id = filter_input(INPUT_GET, 'id');
....

关于php - 在PHP中为外部函数定义$ id，我们在Stack Overflow上找到一个类似的问题： https://stackoverflow.com/questions/53402043/

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Answer 1

您没有从GET variable获取id。

function listGoalkeepersForTeam() {
//insert line
$id = filter_input(INPUT_GET, 'id');
....