php学习笔记（十六）登录页面实例-输入检查和粘性表单

粘性表单会记住输入到其中的值，当用户输入错误而没能准确完成表单，从而需要重新提交时，可能就需要使用粘性表单了。表单第一次运行时什么都不打印，因为变量没有值，如果表单在提交后再次出现，则用户之前的输入会自动显示出来。

welcome to register
";

//添加css样式,错误信息显示红色
print '';

//检查表单是否提交
if ($_SERVER['REQUEST_METHOD'] == 'POST')
{
	$problem = false;//指示是否有错误
	
	//检查每一个值
	if (empty($_POST['firstname']))
	{
		$problem = true;
		print '
please enter your first name
';
	}
	if (empty($_POST['lastname']))
	{
		$problem = true;
		print '
please enter your last name
';
	}
	if(empty($_POST['email']))
	{
		$problem = true;
		print '
please enter your emial
';
	}
	if (empty($_POST['password1']))
	{
		$problem = true;
		print '
please enter password
';
	}
	if (empty($_POST['password2']))
	{
		$problem = true;
		print '
please confirm password
';
	}
	if ($_POST['password1'] != $_POST['password2'])
	{	
			$problem = true;
			print '
confirm did not match password
';
	}
	
	//判断是否有错误发生
	if (!$problem)
	{
		print"
you are now registered
";
	}else
    {
    	print "
please try again
";
    }
}
?>
 
 


	
First Name: 

	
Last Name: 

	
Email Address: 

	
Password: 
	
Confirm Password: