<!doctype html><html><head><meta http-equiv="conent-type" content="text/html" charset="utf-8"/><style>.red{color:red;}</style></head><body><?phpfunction test_input($data){ $data=trim($data); $data=stripslashes($data); $data=htmlspecialchars($data); return $data;}?><?php$name=$email=$web=$comment=$gender="";$nameerr=$emailerr=$weberr=$commenterr=$gendererr="";if($_SERVER[‘REQUEST_METHOD‘]=="POST"){ if(empty($_POST[‘name‘])){ $nameerr="必填名字"; }else{ $name=test_input($_POST[‘name‘]); } if(empty($_POST[‘email‘])){ $emailerr="必填邮件"; }else{ $email=test_input($_POST[‘email‘]); } if(empty($_POST[‘web‘])){ $weberr="必填网址"; }else{ $web=test_input($_POST[‘web‘]); } if(empty($_POST[‘comment‘])){ $commenterr="必填备注"; }else{ $comment=test_input($_POST[‘comment‘]); } if(empty($_POST[‘gender‘])){ $gendererr="必填备注"; }else{ $gender=test_input($_POST[‘gender‘]); }}?><h1>表单验证</h1><span class="red">*必填字段</span><form method="POST" action="<?php echo htmlspecialchars($_SERVER[‘PHP_SELF‘]);?>">名字：<input type="text" name="name"/><span class="red"><?php echo "*".$nameerr;?></span><br/>E-mail：<input type="text" name="email"/><span class="red"><?php echo "*".$emailerr;?></span><br/>网址：<input type="text" name="web"/><span class="red"><?php echo "*".$weberr;?></span><br/>备注：<textarea rows="10" cols="40" name="comment"></textarea><span class="red"><?php echo "*".$commenterr;?></span><br/>性别：<input type="radio" name="gender" value="男"/>男<input type="radio" name="gender" value="女"/>女<span class="red"><?php echo "*".$gendererr;?></span><br/><input type="submit" value="提交验证"/></form><?phpecho "名字".$name;echo "<br/>";echo "E-mail：".$email;echo "<br/>";echo "网址：".$web;echo "<br/>";echo "备注：".$comment;echo "<br/>";echo "性别：".$gender;echo "<br/>";?></body></html>原文：https://www.cnblogs.com/ince/p/10480503.html