php - 可捕获的 fatal error :第6行的类mysqli_result的对象无法转换为字符串

Question

这是脚本：

<?php
       session_start();

    $walldir = mysqli_query($connect, "SELECT `launcherwallpaper` from user where `username` = '$id'");
    $wallpaper = '../../user/'.$_SESSION['username'].'/'.$walldir;
    echo  "<style>head { 
      background: url('".$wallpaper."') no-repeat center center fixed; 
      -webkit-background-size: cover;

      -moz-background-size: cover;
      -o-background-size: cover;
      background-size: cover;
    }</style>";
?>

和数据库数据：

launcherwallpaper
Image/default.jpg

谁能帮助我，谢谢！

Answer 1

这就是你要做的

 $walldir = mysqli_query($connect, "SELECT `launcherwallpaper` from user where `username` = '$id'");
$result_set = mysqli_fetch_assoc($walldir);

$wallpaper = '../../user/'.$_SESSION['username'].'/'.$result_set['launcherwallpaper'];

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