CSF.Zpt.Tales.ITalesPathHandler Interface Reference

Interface for a type which provides custom handling of a TALES path fragment. More...

Inheritance diagram for CSF.Zpt.Tales.ITalesPathHandler:

Public Member Functions
bool	HandleTalesPath (string pathFragment, out object result, IRenderingContext currentContext)
	Gets an System.Object based upon a TALES path fragment. More...

Detailed Description

Interface for a type which provides custom handling of a TALES path fragment.

Member Function Documentation

bool CSF.Zpt.Tales.ITalesPathHandler.HandleTalesPath	(	string	pathFragment,
		out object	result,
		IRenderingContext	currentContext
	)

Gets an System.Object based upon a TALES path fragment.

This method should return a System.Object which represents the traversal of a single-level TALES path fragment, from the current instance. The value of that fragment is passed via the name pathFragment .

The precise meaning of 'traversal' is left to the implementation, but typical semantics will see an object return an associated object from an object graph.

In this simple example, the Employee class may return data from a related Person object, without exposing the Person object directly. This might be because (as shown in this example), the API of that Person object is more complex than desired, and so TALES should see a simplified version.

public class Employee : ITalesPathHandler
{
  private Person _person;

  public bool HandleTalesPath(string pathFragment, out object result, RenderingContext currentContext)
  {
    switch(pathFragment)
    {
    case: "name";
      result = _person.Name;
      return true;
    case: "address";
      result = _person.Address.FullAddress;
      return true;
    case: "gender":
      result = _person.Gender.ToString();
      return true;
    default:
      result = null;
      return false;
    }
  }
}

Note that the return value does not need to be a primitive type. It may be a complex object, and the return value may also implement ITalesPathHandler if desired.

Returns

true if the path traversal was a success; false otherwise.

Parameters

pathFragment	The path fragment.
result	Exposes the result if the traversal was a success
currentContext	Gets the current rendering context.

Implemented in CSF.Zpt.Rendering.RepetitionInfo, CSF.Zpt.Tales.BuiltinContextsContainer, CSF.Zpt.MVC.Tales.MvcContextsContainer, CSF.Zpt.Rendering.RepetitionMetadataCollectionWrapper, and CSF.Zpt.Rendering.OriginalAttributeValuesCollection.

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The documentation for this interface was generated from the following file:

• /home/craig/Projects/CSF.Zpt/CSF.Zpt.Abstractions/Tales/ITalesPathHandler.cs