Using addSuccess and addError to show message in Magento

When working with form, you usually show a message after each action of users. Magento provides a very easy way to show error or success message. Below is an example:

How to do that? I’ll explain for you by creating a simple module called “Message”.

• Step 1: Use ModuleCreator to create a module structure files.
• Step 2: Create a model file called Session

  
  class Magestore_Message_Model_Session extends Mage_Core_Model_Session_Abstract {
  	public function __construct() {
  		$this->init('message');
  	}
  }
  

• Step 3:

  
  <div class="page-head">
      <h3><?php echo $this->__('Demo for message control') ?></h3>
  </div>
  
  <?php echo $this->getMessagesBlock()->getGroupedHtml() ?>
  
  <?php
  	$type = 0;
  	if(isset($_GET['type']))
  	{
  		$type = $_GET['type'];
  	}
  ?>
  
  <form action="" method="get">
  <?php echo $this->__('Please choose message type: ') ?> <br/>
       <input type="radio" name="type" value="1" <?php echo ($type==1)?"checked='checked'":"" ?>> <?php echo $this->__('Error message ') ?><br/>
  <input type="radio" name="type" value="2" <?php echo ($type==2)?"checked='checked'":"" ?>> <?php echo $this->__('Success message ') ?>
  
  <input type="submit" name="submit" value="Submit">
  </form>
  

  In that file, you can see a piece of code to display the message:

  $this->getMessagesBlock()->getGroupedHtml();

• Step 4: Edit action index in Magestore_Message_IndexController

  
  $type = $this->getRequest()->getParam('type');
  
  if(!empty($type))
  {
  switch($type)
  {
  case 1:
  Mage::getSingleton('message/session')->addError($this->__('You have choosen error option'));
  
  break;
  
  case 2:
  Mage::getSingleton('message/session')->addSuccess($this->__('You have choosen success option'));
  
  break;
  }
  }
  
  $this->loadLayout();
  
  $this->_initLayoutMessages('message/session');
  
  $this->renderLayout();
  }
  }
  

  Please look at three bold lines in the code above.

  Finish!!!