本文主题：如何在 Magento 2 中设置和移除会话，将会帮助您了解通过运行代码快速设置和移除会话的方法，因为随着自定义 Magento 2 的开发，了解会话是非常有必要的。
首先，请看下面列出的 Magento 2 的会话类型：
vendor/magento/module-catalog/Model/Session.php
vendor/magento/module-newsletter/Model/Session.php
vendor/magento/module-persistent/Model/Session.php
vendor/magento/framework/Message/Session.php
vendor/magento/module-customer/Model/Session.php
vendor/magento/module-backend/Model/Session.php
vendor/magento/module-checkout/Model/Session.php
接下来，通过以下代码开始调用 Catalog，Customer 和 Checkout 会话。
<?php
namespace Mageplaza\HelloWorld\Block;
class HelloWorld extends \Magento\Framework\View\Element\Template
{
protected $_catalogSession;
protected $_customerSession;
protected $_checkoutSession;
public function __construct(
\Magento\Backend\Block\Template\Context $context,
\Magento\Catalog\Model\Session $catalogSession,
\Magento\Customer\Model\Session $customerSession,
\Magento\Checkout\Model\Session $checkoutSession,
array $data = []
)
{
$this->_catalogSession = $catalogSession;
$this->_checkoutSession = $checkoutSession;
$this->_customerSession = $customerSession;
parent::__construct($context, $data);
}
public function _prepareLayout()
{
return parent::_prepareLayout();
}
public function getCatalogSession()
{
return $this->_catalogSession;
}
public function getCustomerSession()
{
return $this->_customerSession;
}
public function getCheckoutSession()
{
return $this->_checkoutSession;
}
}
?>
然后，通过 .phtml 文件，可以对 Catalog，Customer 和 Checkout 会话进行设置。
$block->getCatalogSession()->setMyName('Mageplaza');
echo $block->getCatalogSession()->getMyName() . '<br />'; // output: Mageplaza
$block->getCheckoutSession()->setTestData('Hello World');
echo $block->getCheckoutSession()->getTestData() . '<br />'; // output: Hello World
$block->getCheckoutSession()->setTestHello('Test Hello Value');
echo $block->getCheckoutSession()->getTestHello() . '<br />'; // output: Test Hello Value
如果要移除这些会话，请执行以下操作：
$block->getCatalogSession()->unsMyName();
$block->getCheckoutSession()->unsTestData();
$block->getCustomerSession()->unsTestHello();
特别的是，用户会话允许收集用户的信息，例如客户名称和邮箱。
// get customer data
if ($block->getCustomerSession()->isLoggedIn()) {
$customerId = $block->getCustomerSession()->getCustomerId();
$customerData = $block->getCustomerSession()->getCustomer();
echo $customerId . '<br />';
echo $customerData->getFirstname() . ' ' . $customerData->getLastname() . '<br />';
echo $customerData->getEmail() . '<br />';
print_r($block->getCustomerSession()->getCustomer()->getData());
}
Checkout（结账）会话可以显示价格信息。
// get checkout session data
echo $block->getCheckoutSession()->getQuoteId();
print_r($block->getCheckoutSession()->getQuote()->getData());