Convert Method to Indexer refactoring This refactoring helps you convert methods that access collections into indexers and update method usages accordingly. You can apply it to:
A method with return value and one or more parameters to convert it into the get
accessor of an indexer with the same set of parameters. A method with void
return type and two or more parameters (the last of which is expected to be a value and the others represent the index) to convert it into the set
accessor of an indexer. If an indexer with only one of the accessors exists, the refactoring will try to add the second accessor if the converted method fits.
Consider the following example:
Before refactoring Applied to 'GetBookAt' Then applied to 'InsertBookAt' class TestBookLibrary
{
private Book [] books ;
public Book GetBookAt ( int index )
{
if ( index >= books . Length )
throw new IndexOutOfRangeException ();
return books [ index ];
}
public void InsertBookAt ( int index , Book book )
{
if ( index >= books . Length )
throw new IndexOutOfRangeException ();
books [ index ] = book ;
}
public void TestCopyBook ( int copy , int to )
{
InsertBookAt ( to , GetBookAt ( copy ));
}
}
class TestBookLibrary
{
private Book [] books ;
public Book this [ int index ]
{
get
{
if ( index >= books . Length )
throw new IndexOutOfRangeException ();
return books [ index ];
}
}
public void InsertBookAt ( int index , Book book )
{
if ( index >= books . Length )
throw new IndexOutOfRangeException ();
books [ index ] = book ;
}
public void TestCopyBook ( int copy , int to )
{
InsertBookAt ( to , this [ copy ]);
}
}
class TestBookLibrary
{
private Book [] books ;
public Book this [ int index ]
{
get
{
if ( index >= books . Length )
throw new IndexOutOfRangeException ();
return books [ index ];
}
set
{
if ( index >= books . Length )
throw new IndexOutOfRangeException ();
books [ index ] = value ;
}
}
public void TestCopyBook ( int copy , int to )
{
this [ to ] = this [ copy ];
}
}
To convert a method to an indexer Place the caret at the declaration or a usage of a method in the editor, or select it in the Structure window . Do one of the following: Press Ctrl+Shift+R and then choose Convert Method to Indexer Choose in the main menu. If no conflicts are found, Rider performs the refactoring immediately. Otherwise, it prompts you to resolve conflicts . Right after the refactoring has been completed, all changes that it makes anywhere, including other files, are registered as a single operation. So you can use the Undo action (Ctrl+Z ) to roll back all these changes with a single keystroke.
Last modified: 11 October 2017