Compress to/Expand Null Coalescing Operation

• Aug 03, 2020
• 2 minutes to read

Purpose

Converts a ternary expression to an equivalent null coalescing operation and vice versa. Use of the null coalescing operations is the most compact way to specify null expressions in C#.

Availability

• The Compress to Null Coalescing Operation Refactoring is available when the caret is inside a “? :“ operator (short form of if). The operator should compare a variable to null. The same variable should be one of two alternative results.
• The Expand Null Coalescing Operation is available when the caret is on a statement that uses the ?? operator.

Usage

1. Place the caret on a compressible ternary expression.

   Note

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

   C#

   private string CheckText(string text){
       return (│text != null ? text : "null");
   }
   

2. Press the Ctrl + . or Ctrl + ~ shortcut to invoke the Code Actions menu.
3. Select Compress to Null Coalescing Operation from the menu (Expand Null Coalescing Operation if you are expanding the null coalescing operation).

After execution, the Refactoring compresses a ternary expression to an equivalent null coalescing operation or expands the null coalescing operation into an equivalent ternary expression.

C#

private string CheckText(string text){
    return (text ?? "null");
}