Declare Interface

• Jul 21, 2021
• 2 minutes to read

Purpose

Generates an interface for reference to a non-existent type and adds the interface members referenced from the initial code to it. The interface is declared in a new source code file (the default behavior).

This code provider can drop a marker onto the initial interface reference, if the interface is created in a new file (the default behavior) and the Markers feature is enabled.

See the following topic section for more details: Markers: How to Enable

Availability

Available when the caret is on the interface name if the interface declaration does not exist.

Usage

1. Place the caret on a reference to non-existent interface.

   Note

   The blinking cursor shows the caret’s position at which the Code Provider is available.

   C#

   //Filename: Program.cs
   class Program {
       static void Main() {
           IPerson│ Andrew = new Customer("Andrew", "Fuller");
           Andrew.Age = 47;
           Andrew.SaveToDB();
       }
   }
   

   VB.NET

   'Filename: Program.vb
   Friend Class Program
       Shared Sub Main()
           Dim Andrew As │IPerson = New Customer("Andrew", "Fuller")
           Andrew.Age = 47
           Andrew.SaveToDB()
       End Sub
   End Class
   

2. Press the Ctrl + . or Ctrl + ~ shortcut to invoke the Code Actions menu.

3. Select Declare | Interface from the menu.

   

After execution, the code provider adds a new file to the project and declares the interface in it.

C#

//Filename: IPerson.cs
public interface IPerson {
    void SaveToDB();
    int Age { get; set; }
}

VB.NET

'Filename: IPerson.vb
Public Interface IPerson
    Sub SaveToDB()
    Property Age() As Integer
End Interface

Customization

Change Code Actions Settings

You can configure the Declare Interface code provider settings on the Editor | C# (Visual Basic) | Code Actions | Code Actions Settings options page.

For example, specify the “Position of newly-generated type declarations” setting to configure where CodeRush should place the newly-generated type declarations. The possible options are:

• Above the current type
• Below the current type
• Create a new file (the default value)

For more information, refer to the following topic: Code Actions Settings.

Change Scope

You can also change the default visibility modifier of the generated type and its members on the Editor | C# (Visual Basic) | Scope Options options page.

See the following topic for details: Scope.