Question

<?php 
    if($_POST) {
         //not empty
         //atleast 6 characters long

         $errors = array();
         //start validation
         if(empty($_POST['email'])) {
             $errors['email1'] = "<p style='color:red;font-family: BCompset, Arial, Helvetica, sans-serif;font-size:30px;'>Please write down your email!</p>";
         }

         //check errors
         if(count($errors) == 0) {
             //redirect to success pages
             header("Location: success.php");
             exit();
          }
    }

    ?>
    <form action="" method="POST" class="searchform" dir="ltr">
      <input type="text" name="email" placeholder="Your email address"/>
      <button name="submit" type="submit" class="btn btn-default"><i class="fa fa-arrow-circle-o-right"></i></button>
      <p><?php if(isset($errors['email1'])) echo $errors['email1']; ?></p>
      <?php if(count($errors) == 0){
         echo "<p id='para' dir='rtl'>
         You can add your email to get the latest updates.</p>";
       } ?>
    </form>

我希望在尚未提交表单时显示带有id ='para'（第31行）的段落，如果用户在未输入其电子邮件地址的情况下点击了提交按钮，则会弹出错误消息，该段落将不再显示..要做到这一点，我设置if(count($errors) == 0)，但我在第31行得到未定义变量错误消息。也许是因为我不能从动作脚本中取一个变量，直到表单没有提交。请解决我的问题？

Answer 1

试试这段代码： -

<?php 
 $errors = array();
if($_POST)
    {
        //not empty
        //atleast 6 characters long
        //start validation

        if(empty($_POST['email']))
        {
            $errors['email1'] = "<p style='color:red;font-family: BCompset, Arial, Helvetica, sans-serif;font-size:30px;'>Please write down your email!</p>";
        }

        //check errors
        if(count($errors) == 0)
        {
            //redirect to success pages
            header("Location: success.php");
            exit();
        }
    }

?>
<form action="" method="POST" class="searchform" dir="ltr">
                                <input type="text" name="email" placeholder="Your email address"/>
                                <button name="submit" type="submit" class="btn btn-default"><i class="fa fa-arrow-circle-o-right"></i></button>
                                <p><?php if(isset($errors['email1'])) echo $errors['email1']; ?></p>
                   <?php if(count($errors) == 0){echo "<p id='para' dir='rtl'>You can add your email to get the latest updates.</p>";}?>
</form>

Answer 2

问题是您的<form>超出了if($_POST)，因此会显示是否设置了$_POST。但$errors仅在if内设置。有两种简单的方法可以解决这个问题：

将$errors的初始化移至if之前。
使用if(empty($errors)代替if(count($errors) == 0)。如果变量未设置，empty()不会抱怨。

从动作表单脚本中检索变量时未定义的变量

2 个答案: