如何檢查表單中的任何字段是否爲空在php

Question

每當我提交我的表單中的內容我想檢查是否有任何字段爲空。到目前爲止，我有什麼不工作

$firstname = $_POST['firstname']; 
$lastname = $_POST['lastname']; 
$username = $_POST['username']; 
$password = $_POST['password']; 
$passwordconf = $_POST['passwordconf']; 
$email = $_POST['email']; 
$securityq = $_POST['securityq']; 
$qanswer = $_POST['qanswer']; 

if(empty($firstname) || empty($lastname) || empty($username) || empty($password) || empty($passwordconf) || empty($email) || empty($securityq) || empty($qanswer)) 
{ 
    echo "You did not fill out the required fields."; 
} 

和形式

<form name="registrationform" action="register.php"> 
    First Name:<input type="text" name="firstname"> 
    Last Name:<input type="text" name="lastname"> 
    Email:<input type="text" name="email"> 
    Username:<input type="text" name="username"> 
    Password:<input type="password" name="password"> 
    Confirm Password:<input type="password" name="passwordconf"> 
    Security Question:<input type="text" name="securityq"> 
    Answer:<input type="text" name="qanswer"> 
    <input type="submit" name="submit" value="Register"> 
</form> 

和繼承人爲登記註冊頁面，如果有幫助http://www.myjournal.tk/register.html

Answer 1

表單缺少方法...

<form name="registrationform" action="register.php" method="post"> //here 

anywyas查看發佈的數據你可以使用isset() ..

確定是否一個變量被設定，並沒有NULL

if(!isset($firstname) || trim($firstname) == '') 
{ 
    echo "You did not fill out the required fields."; 
} 

Answer 2

Specify POST method in form 
<form name="registrationform" action="register.php" method="post"> 


your form code 

</form>