Declare Field

• Aug 25, 2021
• 2 minutes to read

Purpose

Creates a field declaration for an undeclared reference. This code provider defines the field type based on the selected reference. You can use this code provider for Test-Driven Development.

The Declare Field provider can drop a marker onto the initial constant reference, 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 variable reference.

Usage

1. Place the caret in an undeclared variable (“testFailedText” in this example).

   C#

   class TestClass
   {
      public bool Test()
      {
         //...
         Console.WriteLine("[ERROR]" + testFailedText);
         return false;
      }
   }
   

   VB.NET

   Class TestClass
       Public Function Test() As Boolean
           Console.WriteLine("[ERROR]" & testFailedText)
           Return False
       End Function
   End Class
   

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

   

3. Select Declare | Field 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, the code provider adds the field declaration to the current class and moves the caret to the field type.

C#

class TestClass
{
   public bool Test()
   {
      //...
      Console.WriteLine("[ERROR]" +  testFailedText);
      return false;
   }
   string testFailedText;
}

VB.NET

Class TestClass
    Public Function Test() As Boolean
        Console.WriteLine("[ERROR]" & testFailedText)
        Return False
    End Function
    Dim testFailedText As String
End Class

Blazor Support

The Declare Field code provider is available from the @code section and markup of .razor files.
For example, run this provider from Razor markup to create a field for the active Blazor component:

Note

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

Customization

Change Scope

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

For example, set the default scope for declared field to “Public”. The Declare Field provider creates a field with the public visibility, as shown below:

C#

public string testFailedText;

VB.NET

Public testFailedText As String

See the following topic for details: Scope.