无法将文本值上传到mysql

Question

每次我提交我的网站表格时，它只会创建一个新ID。但是所有其他值都是空的，我该怎么办？

<?php
error_reporting(E_ALL);ini_set('display_errors',1); 

$servername = "localhost";
$username = "seamaszhou";
$password = "123456";
$dbname = "guest";




$conn = new PDO("mysql:host=$servername;dbname=$dbname", $username, 
$password);
// set the PDO error mode to exception
$conn->setAttribute(PDO::ATTR_ERRMODE, PDO::ERRMODE_EXCEPTION);

// prepare sql and bind parameters
$stmt = $conn->prepare("INSERT INTO guest 
(guestName,guestEmail,guestContent) 
VALUES (:guestName, :guestEmail, :guestContent)");

$stmt->bindParam(':guestName', $guestName);
$stmt->bindParam(':guestEmail', $guestEmail);
$stmt->bindParam(':guestContent', $guestContent);

// insert a row
$guestName = "$guestName";
$guestContent = "$guestContent";
$guestEmail = "$guestEmail";
$stmt->execute();



?>

Answer 1

因为您没有设置任何值。当你这样做时：

$guestName = "$guestName";

变量$guestName被设置为包含变量$guestName的当前值的字符串。由于它不包含任何内容，因此您只需将其设置为空字符串。

使用实际值。例如：

$guestName = "Some name";

或者，如果您真的希望将变量名称作为字符串，请使用单引号，这样它就不会被解释为变量：

$guestName = '$guestName';