PHP MySQL查询未返回结果

我正在做一个学校项目，但我的代码在运行时只返回ann HTTP 500错误。PHP和MySQL已正确安装并正常工作。我已经使用INSERT命令对此进行了测试

我的代码：

<?php


// Some inputvalues (those are correct)
$user = "";
$pass = "";
$host = "";
$db = "";

$conn = mysqli_connect($host, $user, $pass, $db)
    or die("Het is niet gelukt om te verbinden met de database!");


// Vaststellen wat je wil weten
$grab = $_GET['grab'];

$query = "SELECT * FROM informaticaproject WHERE id=1";
$result = mysqli_query($conn, $query)
    or die("Geen gegevens opgehaald!");

echo $result;

while ($row = mysqli_fetch_assoc($result)) {
    $anwer = $row["'" . $grab . "'"];
}

echo $answer;


mysqli_close($conn);

//试试这个
$anwer=$row[$grab]试试这个。应该有用。这不是编码问题，
echo$answer分配给
应答
并检查
应答
。学会有耐心。@RahulMeshram谢谢你，但这不管用。问题是我没有得到任何结果。请先调试！一行一行地走<代码>打印（$result）
或尝试插入
echo 1介于两者之间。启用。从你自己开始。你能做到。
//Try This

<?php


// Some inputvalues (those are correct)
$user = "";
$pass = "";
$host = "";
$db = "";

$conn = mysqli_connect($host, $user, $pass, $db)
    or die("Het is niet gelukt om te verbinden met de database!");


// Vaststellen wat je wil weten
$grab = $_GET['grab'];

$query = "SELECT * FROM informaticaproject WHERE id=1";
$result = mysqli_query($conn, $query)
    or die("Geen gegevens opgehaald!");

echo $result;

while ($row = mysqli_fetch_assoc($result)) {
    $anwer = $row["'" . $grab . "'"];
}

echo $anwer;


mysqli_close($conn);