Question

我正在尝试创建一条错误消息，以防用户没有正确填写字段，但是在第一次加载页面时，我希望它不显示任何错误消息，但是它会在按下按钮之前执行代码，因此它会在用户执行任何操作之前显示一条错误消息...

我该如何解决呢？

<!DOCTYPE html>
<html lang="en" dir="ltr">
  <head>
    <meta charset="utf-8">
    <title>ROCK PAPER SCISSORS GAME</title>
  </head>
  <style media="screen">
    input[type=text], select{
      width: 100%;
      padding: 5px;
      margin: 10px;
      height: 20px;
      border-radius: 5px;

    }
    input[type=password]{
      width: 100%;
      padding: 5px;
      margin: 10px;
      height: 20px;
      border-radius: 5px;
    }
    input[type=submit]{
      margin-left: 10px;
      width: 150px;
      height: 30px;
      background-color: #6DC066;
      border-radius: 15px;
    }
    input[type=submit]:hover {
      background-color: #45a049;
    }

    input:hover {
      border-color: #26c8ff;
      border-width: 3px;

    }

  </style>
  <?php

    $responseMessage = "";

    if (!empty($_POST["email"]) && !empty($_POST["pass"])){
      $responseMessage = "they are set";

    } else if (empty($_POST["email"]) && empty($_POST["pass"])){
      $responseMessage = "please, fill in all fields";

    }

   ?>

  <body>
    <div style="width: 550px;">
    <h1 style="margin-left: 10px;">LOGIN ROCK SCISSORS GAME:</h1>
    <p style="margin-left: 10px; color: red"><?= $responseMessage; ?></p>

    <form class="" action="index.php" method="post">
      <label style="margin: 10px;" for="email" >Email:</label>
      <input type="text" name="email" value="" placeholder="Type your email">
      <label style="margin: 10px;" for="pass">Password:</label>
      <input type="password" name="pass" value="" placeholder="Type your password">
      <input type="submit" name="login" value="login">
  </form>
</div>

  </body>
</html>

Answer 1

在运行代码之前，请检查表单是否已提交（通过检查“提交”按钮是否存在）。

<?php

$responseMessage = "";

// This check will only evaluate as true if $_POST['login'] exits and isn't null, 
// which will only be the case when the form been submitted.
if (isset($_POST['login'])) {

    if (!empty($_POST["email"]) && !empty($_POST["pass"])){
        $responseMessage = "they are set";

    } else if (empty($_POST["email"]) && empty($_POST["pass"])){
        $responseMessage = "please, fill in all fields";

    }
}
?>

Answer 2

您需要检查发帖请求

<?php
    $responseMessage = "";
    if ($_POST && $_POST["login"]){
        if (!empty($_POST["email"]) && !empty($_POST["pass"])){
            $responseMessage = "they are set";
        }else if (empty($_POST["email"]) || empty($_POST["pass"])){
            // i changed && to || (or)
            $responseMessage = "please, fill in all fields";
        }
    }
?>

我点击提交按钮后，如何在php上执行代码？

2 个答案: