Across a site we will have to reuse certain view elements so a better way is to provide grouping of repeated complex code to a separate class or file and use it anywhere with a much shorter statement across a site. When we are working with view in zend framework the shorter statement which is used to access a complex code is referred as partial or view helpers.
Zend Partial template and Helper class
Zend gives the power to render a partial template or use a helper class for the purpose of reusing the same code in multiple view scripts. Both of these approaches have a lot in common. Both allow you to render components conditionally, modifying behavior based on the element you are working with. Both let you generate HTML using attributes of the objects that you’re interacting with. This gives you the ability to view each helper or partial as a treatment of a single item in, for instance, an array of objects. Both can be used in one single piece of code for the same or similar operations in multiple view scripts.
When you work with a view helper, you are working with a class that is adding functionality to your default view instance. With the helper registered to the view, calling its main method serves to instantiate it as well as run it. This means you don’t have to directly instantiate it first; the view instance does that. Because helpers are registered to the view, as well as the other functionalities built out in Zend_View_Helper_Abstract, you are able to call other helpers within the helper you’re working with. This makes it easier to employ useful design patterns when building out modules within the view. In general, it also allows you to modify the behavior of the helper based on global variables assigned to the view from the controller.
A partial is a reusable template that is rendered by a special type of helper — in its most basic case, the partial helper class. When using a partial, you explicitly bind variables to a local scope that only work within the context of the template you define it has no access to the global view, and therefore can only operate on the variables provided to it as well as information it can pull out of places like Zend_Registry if you need to define a handful of variables only to be used in the context of a repeatable template, you can rope them off to their own file and not worry about making your code harder to read or affecting any data outside of this specific context.
View Helper Vs Partial Template
The difference in scope between a partial rendered by the partial helper and a custom helper class is that you have to explicitly feed variables to it. If you’re doing MVC, this means that anything you are getting out of the model will be fed to the view by the controller, and then finally to the partial helper. On the other hand, in some cases, business logic may require special cases for display that would be unwieldy to determine for each controller action. You may want to assign data to the view in the controller class’s __init () function regardless of what action you are taking. By accessing the view instance as an attribute of your custom helper, there’s one less piece of data you have to explicitly worry about when implementing your view script.