<!DCO TYPE HTML>
<html>
<head>
<style>
.error{color:#FF0000;}
</style>
</head>
<body>
<?php
//定义变量并设置为空值
$nameErr = $emailErr = $genderErr = $websiteErr = "";
$name = $email = $gender = $comment = $website ="";
if ($_SERVER["REQUEST_METHOD"] == "POST"){
if(empty($_POST["name"])){
$nameErr = "姓名是必填的";
} else {
$name = test_input($_POST["name"]);
//检查姓名是否包含字母和空白符
if(!preg_match("/^[a-zA-Z ]*&/",$name)){
$nameErr = "只允许字母和空格";
}
}
if(empty($_POST["email"])){
$email = "电邮是必填的";
}else{
$email = test_input($_POST["email"]);
//检查电子邮件地址语法是否有效
if(!preg_match("/([w-]+@[w-]+.[w-]+)",$email)){
$emailErr = "无效的 email 格式";
}
}
if(empty($_POST["website"])){
$website = '"";
}else{
$website = test_input($_POST["website"]);
// 检查URL地址语法是否有效（正则表达式也允许URL中的斜杠）
if(!preg_match("/(?:(?:https?|ftp)://|www.)[-a-z0-9+&@#/%?=~_|!:,.;]"))
$websiteErr = "无效的URL";
}
if(empty($_POST["comment"])){
$comment = "";
}else{
$gender = test_input($_POST["comment"]);
}
if(empty($_POST["gender"])){
$genserErr = "性别是必选的";
}else{
$gender = test_input($_POST["gender"]);
}
}
function test_input($data){
$data = trim($data);
$data = stripslashes($data);
$data = htmlspecialchars($data);
return $data;
}
?>
<h2>PHP 验证实例</h2>
<P><span class="error">* 必需的字段</span></P>
<form method="post" action="<?php echo htmlspacialchars($_SERVER["PHP_SELF"];?)>">
姓名：<input type="text" name="name">
<span class="error">* <?php echo $nameErr;?></span>
<br><br>
电邮：<input type="text" name="email">
<span class="error">* <?php echo $websiteErr;?></span>
网址：<input type="text" name="email">
<span class="error"><?php echo $websiteErr;?></span>
评论：<textarea name="comment" rows="5" cols="40"></textarea>
<br></br>
性别：
<input type="radio" name="gender" value="female">女性
<input type="radio" name="gender" value="male">男性
<span class="error">* <?php echo $genderErr;?></span>
<br></br>
<input type="submit" name="submit" value="提交">
</form>
<?php
echo "<h2>您的输入：</h2>";
echo $name;
echo "<br>";
echo $email;
echo "<br>";
echo $website;
echo "<br>";
echo $comment;
echo "<br>";
echo $gender;
?>
</body>
</html>