<?php header("Content-type:text/html;charset=utf-8"); // 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字符 if (!preg_match("/^[a-zA-Z ]*$/",$name)) { $nameErr = "只允许字母和空格"; } } if (empty($_POST["email"])) { $emailErr = "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+&@#/%?=~_|!:,.;]*[-a-z0-9+&@#/%=~_|]/i",$website)) { $websiteErr = "无效的 URL"; } } if (empty($_POST["comment"])) { $comment = ""; } else { $comment = test_input($_POST["comment"]); } if (empty($_POST["gender"])) { $genderErr = "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 $data; } ?> <!DOCTYPE html> <html> <head> <meta charset="UTF-8"> <title></title> </head> <body> <div style="350px;height:1000px;margin:0 auto;"> <h2>PHP 验证实例</h2> <p><span class="error">* 必需的字段</span></p> <form method="post" action="<?php echo htmlspecialchars($_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 $emailErr;?></span> <br><br> 网址：<input type="text" name="website"> <span class="error"><?php echo $websiteErr;?></span> <br><br> 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> </body> </html> <?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; ?>