Declare Method

• Aug 25, 2021
• 3 minutes to read

Purpose

Generates a method with appropriate parameters for an undeclared method call. You can use this code provider in Test-Driven Development.

The Declare Method provider adds a method declared in the interface to all its implementers.

This provider can also drop a marker onto the method call if the Marker feature is enabled. See the following topic section for more details: Markers: How to Enable.

Availability

Available when the caret is in an undeclared method.

Usage

1. Place the caret in an undeclared method’s name (“GetCurrencyRate” in this example).

   C#

   public class Sample 
   {
       public static double ConvertToUSD(double amount, object source)
       {
           return amount / GetCurrencyRate(source);
       }
       static void Main(string[] args)
       {
           double price = ConvertToUSD(10, null);
       }
   }
   

   VB.NET

   Class Sample
       Public Shared Function ConvertToUSD(amount As Double, source As Object) As Double
           Return amount / GetCurrencyRate(source)
       End Function
       Shared Sub Main(ByVal args() As String)
           Dim price As Double = ConvertToUSD(10, Nothing)
       End Sub
   End Class
   

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

   

3. Select Declare Method from the menu and press Enter. A red target picker marker appears that allows you to choose the place where the generated code can be inserted.

   

   You can configure the Target Picker on the Editor | All Languages | Code Actions | Target Picker options page.

   

4. Use the Up Arrow and Down Arrow keys to move the target picker.

5. Press Enter to generate a code in the selected place.

After execution, this code provider adds the method declaration to the class/interface. In the example below, the Declare Method provider added the not-implemented GetCurrencyRate () method to the Sample class:

C#

public class Sample 
{
    public static double ConvertToUSD(double amount, object source)
    {
        return amount / GetCurrencyRate(source);
    }
    static void Main(string[] args)
    {
        double price = ConvertToUSD(10, null);
    }
    static double GetCurrencyRate(object source)
    {
        throw new NotImplementedException();
    }
}

VB.NET

Class Sample
    Public Shared Function ConvertToUSD(amount As Double, source As Object) As Double
        Return amount / GetCurrencyRate(source)
    End Function
    Shared Sub Main(ByVal args() As String)
        Dim price As Double = ConvertToUSD(10, Nothing)
    End Sub
    Private Shared Function GetCurrencyRate(ByVal source As Object) As Double
        Throw New NotImplementedException
    End Function
End Class

Blazor Support

The Declare Method code provider is available from the @code section and markup of .razor files:

Note

If a Razor code-behind file (.razor.cs) exists, the Declare Method code provider adds the declared method to this file instead of the @code section.

Customization

Change Code Actions Settings

You can configure the default body of newly-generated methods on the Editor | C# (Visual Basic)| Code Actions | Code Actions Settings options page. The default value is “Throw NotImplementedException instance”.

Refer to the following topic for more information: Code Actions Settings.

Change Scope

You can change the default visibility modifier of a declared method on the Editor | C# (Visual Basic) | Scope Options options page.

For example, set the default scope for this method to “Protected”. The code provider declares a method with the protected visibility, as shown below:

C#

protected static double GetCurrencyRate(object source)
{
    throw new NotImplementedException();
}

VB.NET

Protected Shared Function GetCurrencyRate(ByVal source As Object) As Double
    Throw New NotImplementedException
End Function

See the following topic for details: Scope.