本章節我們將介紹如何使用PHP驗證客戶端提交的表單數據。
PHP 表單驗證
本章節我們將展示PHP表單數據安全處理，為了防止黑客及垃圾信息我們需要對表單進行數據安全驗證。
在本章節介紹的HTML表單中包含以下輸入字段： 必須與可選文本字段，單選按鈕，及提交按鈕：
實例
<!DOCTYPE HTML>
<html>
<head>
<meta charset="utf-8">
<title>php.cn</title>
<style>
.error {color: #FF0000;}
</style>
</head>
<body>
<?php
// 定義變量并默認設置為空值
$nameErr = $emailErr = $genderErr = $websiteErr = "";
$name = $email = $gender = $comment = $website = "";
if ($_SERVER["REQUEST_METHOD"] == "POST")
{
if (empty($_POST["name"]))
{
$nameErr = "名字是必需的";
}
else
{
$name = test_input($_POST["name"]);
// 檢測名字是否只包含字母跟空格
if (!preg_match("/^[a-zA-Z ]*$/",$name))
{
$nameErr = "只允許字母和空格";
}
}
if (empty($_POST["email"]))
{
$emailErr = "郵箱是必需的";
}
else
{
$email = test_input($_POST["email"]);
// 檢測郵箱是否合法
if (!preg_match("/([\w\-]+\@[\w\-]+\.[\w\-]+)/",$email))
{
$emailErr = "非法郵箱格式";
}
}
if (empty($_POST["website"]))
{
$website = "";
}
else
{
$website = test_input($_POST["website"]);
// 檢測 URL 地址是否合法
if (!preg_match("/\b(?:(?:https?|ftp):\/\/|www\.)[-a-z0-9+&@#\/%?=~_|!:,.;]*[-a-z0-9+&@#\/%=~_|]/i",$website))
{
$websiteErr = "非法的 URL 的地址";
}
}
if (empty($_POST["comment"]))
{
$comment = "";
}
else
{
$comment = test_input($_POST["comment"]);
}
if (empty($_POST["gender"]))
{
$genderErr = "性別是必需的";
}
else
{
$gender = test_input($_POST["gender"]);
}
}
function test_input($data)
{
$data = trim($data);
$data = stripslashes($data);
$data = htmlspecialchars($data);
return $data;
}
?>
<h2>PHP 表單驗證實例</h2>
<p><span class="error">* 必需字段。</span></p>
<form method="post" action="<?php echo htmlspecialchars($_SERVER["PHP_SELF"]);?>">
名字: <input type="text" name="name" value="<?php echo $name;?>">
<span class="error">* <?php echo $nameErr;?></span>
<br><br>
E-mail: <input type="text" name="email" value="<?php echo $email;?>">
<span class="error">* <?php echo $emailErr;?></span>
<br><br>
網址: <input type="text" name="website" value="<?php echo $website;?>">
<span class="error"><?php echo $websiteErr;?></span>
<br><br>
備注: <textarea name="comment" rows="5" cols="40"><?php echo $comment;?></textarea>
<br><br>
性別:
<input type="radio" name="gender" <?php if (isset($gender) && $gender=="female") echo "checked";?> value="female">女
<input type="radio" name="gender" <?php if (isset($gender) && $gender=="male") echo "checked";?> value="male">男
<span class="error">* <?php echo $genderErr;?></span>
<br><br>
<input type="submit" name="submit" value="Submit">
</form>
<?php
echo "<h2>您輸入的內容是:</h2>";
echo $name;
echo "<br>";
echo $email;
echo "<br>";
echo $website;
echo "<br>";
echo $comment;
echo "<br>";
echo $gender;
?>
</body>
</html>