PHP 表单未正确验证表单字段

标签 php html mysql sql forms

我正在学习更多的 PHP,在 PHP 本身开始工作后,我似乎无法让它正确验证任何表单字段。我的目标是检查 firstname 字段是否为空,如果是,它将以红色显示一条消息。红色的消息有效,但只是因为表单提交正在调用回显脚本,而不是因为它检测到任何空字段,因为当我做了一个 else 语句说“wassup”如果它不为空时,我得到了字段为空时的相同消息。另外,有没有办法像使用 JavaScript 一样一次检查多个输入字段?例如,如果 input1 == '' || input2 == '' 等等。这是我的 HTML:

<html>
<head>
<title>Welcome</title>
</head>
<body>
<form action="welcome.php" method="post">
<fieldset>
<legend>Personal Info</legend>
First name <input name="name" type="text"> 
Middle name <input name="middlename" type="text"> 
Surname <input name="lastname" type="text">  
Age <input name="age" type="number"> 
Date of birth <input name="dob"  type="date">
</fieldset>
<fieldset>
<legend>Regional & location info</legend>
Continent 
<select>
<option value="europe">Europe</option>
<option value="americas">America</option>
<option value="africa">Africa</option>
<option value="asia">Asia</option>
<option value="australia">Australia</option>
<option value="eurasia">Eurasia</option>
</select>
Country <input name="country" type="text"> State <input type="text"> 
City <input name="city" type="text">
Street number <input name="streetno" type="number"> 
Street name <input name="streetname" type="text"> <br><br>
Suburb <input name="suburb" type="text"> Postcode <input name="postcode" type="number"> 
If none of these apply to your accommodations, enter a typed location here <input  type="text">
</fieldset>
<fieldset>
<legend>Previous lifestyle accommodations</legend>
Previous &/or most recent job title <input name="job" type="text"> 
First   time job seeker <input type="checkbox" name="check1" value="ftjb"> 
I'm a student <input type="checkbox" name="check2" value="ias"> 
Previous &/or most recent acedemic title <input name="school" type="text"> 
First time applying for a qualification <input type="checkbox" name="check3" value="ftafaq"> 
I have work experience <input type="checkbox" name="check4" value="ihwe">
</fieldset>
<fieldset>
<legend>Details of arrival</legend>
Reason for arrival <input name="reason" type="text"> 
Date of arrival <input name="arrival" type="date"> 
Amount of stay expectancy 
<input type="checkbox" name="check3">Temporary 
<input type="checkbox" name="check4">Longterm
</fieldset>
<fieldset>
<legend>Signiture</legend>
<input name='signiture' type="text"> 
</fieldset>
<input type="submit" name="submit" value="Submit">
</form>
</body>
</html> 

这是我的 PHP 代码:

<?php
$firstname = $_POST['name'];
$lastname = $_POST['lastname'];
$age = $_POST['age'];
$dob = $_POST['dob'];
$country = $_POST['country'];
$city = $_POST['city'];
$suburb = $_POST['suburb'];
$postcode = $_POST['postcode'];
$streetno = $_POST['streetno'];
$streetname = $_POST['streetname'];
$suburb = $_POST['suburb'];
$job = $_POST['job'];
$school = $_POST['school'];
$reason = $_POST['reason'];
$arrival = $_POST['arrival'];
$signiture = $_POST['signiture'];
if (isset($_POST['submit'])) {
    if (empty($_POST[$firstname])) {
        echo '<p style="color: red; text-align: center">Your first name is required</p>';
    } else {
        echo "wassaup";
    }
}





?>

最佳答案

在您的 if 语句中,您需要这样做:

if (empty($_POST['name'])) {    //Or replace $_POST['name'] with $firstname
    echo '<p style="color: red; text-align: center">Your first name is required</p>';
} else {
    echo "wassaup";
}

关于PHP 表单未正确验证表单字段,我们在Stack Overflow上找到一个类似的问题: https://stackoverflow.com/questions/55157825/

相关文章:

php - 从 PHP 向 Node.js(socket.io) 发送请求

PHP 从数据库中删除项目不起作用

php - 为什么 file_get_contents() Javascript 输出不执行?

javascript - 如何在 asp.net 中使用 JavaScript 只打印表数据元素?

php - 从数据库绘制 Canvas 文本?

mysql - WordPress 插件创建如何执行.sql以便在激活插件时插入多行

javascript - Opcache、APC 或 Session.Upload_Progress 用于从单个文件输入上传多个文件

javascript - 使用 javascript 内联表单标签和字段

html - 样式化的 HTML 元素在打印时看起来不同

javascript - 在php中将数据保存到mysql数据库后,如何在按钮单击中切换选项卡?