不检查用户是否被带走

Question

这段代码没有按照预期进行，我无法理解为什么。请帮忙

$userquery = "SELECT Username FROM Member WHERE Username = '$username'";
$checkUser = mysqli_num_rows($conn, $userquery);
if($checkUser > 0 ){
header("Location:Registration.php?UserError=true&reason=taken" );
}else{

$query = "INSERT INTO Member ( Username, Password, Email, Salt, Verify_Code ) VALUES
( '$username', '$password', '$email', '$salt', '$verify_code' )";
$result = mysqli_query($conn, $query);
}

谢谢大家

Answer 1

您需要执行查询$Result = mysqli_query ($conn , $query);

   <?php 
       $userquery = "SELECT Username FROM Member WHERE Username = '$username'";        
       $Result =  mysqli_query ($conn , $query);
       $checkUser = mysqli_num_rows($Result);
       if($checkUser > 0 ){
        header("Location:Registration.php?UserError=true&reason=taken" );
       }else{

        $query = "INSERT INTO Member ( Username, Password, Email, Salt, Verify_Code ) VALUES
        ( '$username', '$password', '$email', '$salt', '$verify_code' )";
        $result = mysqli_query($conn, $query);
       }

   ?>

Answer 2

使用它：

$queryObj = mysqli_query($conn, $userquery);
$checkUser = mysqli_num_rows($conn, $queryObj);

您没有执行查询。你需要先执行它。