Question

如何在单击“提交”按钮之前阻止显示错误消息？

出于某种原因，'else'语句的内容在页面加载中可见 - 消息“NO”只应在输入“a”之外的其他内容后出现..我做错了什么？

<form method="POST">
  <input type="text" class="textfield" id="cursor" name="pass"> 
  <input type="submit" class="button" name="submit" value="OK"> 
</form>

<?php
$pass = $_POST['pass'];

    if($pass == 'a') {      
        echo "YES";
} 
    else{
        echo "NO";
}
?>

Answer 1

添加此PHP代码：

<?php
if(isset($_POST['pass'])) {
    // your check here
}
?>

Answer 2

测试提交按钮是否在提交的数据中。

if (isset( $_POST['submit'] )) {

Answer 3

<form method="POST">
  <input type="text" class="textfield" id="cursor" name="pass"> 
  <input type="submit" class="button" name="submit" value="OK"> 
</form>

<?php
$pass = $_POST['pass'];
//You need to check if the form is submitted
    if($_POST['submit']){
        if(isset($pass) && !empty($pass) && $pass == 'a') {      
            echo "YES";
    } 
        else{
            echo "NO";
    }
?>

密码中的错误消息在页面加载时可见？

3 个答案: