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This article explains the implementation method of PHP form verification through examples, and shares it with everyone for your reference. The specific content is as follows
1.PHP form processing
welcome.html
<html> <body> <form action="welcome.php" method="post"> Name: <input type="text" name="name"><br> E-mail: <input type="text" name="email"><br> <input type="submit"> </form> </body> </html>
welcome.php
<html> <body> <!--PHP 超全局变量 $_GET 和 $_POST 用于收集表单数据(form-data)--> Welcome <?php echo $_POST["name"]; ?><br> Your email address is: <?php echo $_POST["email"]; ?> </body> </html>
2. Complete example of PHP form verification
<html> <head> </head> <body> <?php // 定义变量并设置为空值 $nameErr = $emailErr = $websiteErr = ""; $name = $email = $website = ""; if ($_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 //preg_match() 函数检索字符串的模式,如果模式存在则返回 true,否则返回 false。 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("/\b(?:(?:https?|ftp):\/\/|www\.)[-a-z0-9+&@#\/%?=~_|!:,.;]*[-a-z0-9+&@#\/%=~_|]/i",$website)) { $websiteErr = "无效的 URL"; } } } function test_input($data) { //去除用户输入数据中不必要的字符(多余的空格、制表符、换行) $data = trim($data); //删除用户输入数据中的反斜杠(\) $data = stripslashes($data); //把特殊字符转换为 HTML 实体 $data = htmlspecialchars($data); return $data; } ?> <h2>PHP 验证实例</h2> <p><span class="error">* 必需的字段</span></p> <!--htmlspecialchars() 函数把特殊字符转换为 HTML 实体。--> <form method="post" action="<?php echo htmlspecialchars($_SERVER["PHP_SELF"]);?>"> <!--value:保留表单中的值--> 姓名:<input type="text" name="name" value="<?php echo $name;?>"> <span class="error">* <?php echo $nameErr;?></span> <br><br> 邮箱:<input type="text" name="email" value="<?php echo $email;?>"> <span class="error">* <?php echo $emailErr;?></span> <br><br> 网址:<input type="text" name="website" value="<?php echo $website;?>"> <span class="error"><?php echo $websiteErr;?></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>"; ?> </body> </html>
I hope this article will help you learn PHP programming.