Using ?? : Nullable « Data Type « C# / CSharp Tutorial

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C# / CSharp Tutorial » Data Type » Nullable

2.54.11.Using ??

using System; 

 

class MainClass { 

  static double myMethod() { 

      Console.WriteLine("In myMethod()."); 

      return 0.0; 

  } 

 

  public static void Main() { 

    double? defaultValue = 1.5; 

    double currentBalance; 

 

    currentBalance = defaultValue ?? myMethod(); 

    Console.WriteLine(currentBalance); 

    

    defaultValue = null; 

    currentBalance = defaultValue ?? myMethod(); 

    Console.WriteLine(currentBalance); 

    

  } 

}

1.5
In myMethod().
0

2.54.Nullable
	2.54.1.	null unification
	2.54.2.	Nullable long
	2.54.3.	Nullable Struct
	2.54.4.	Nullable Types Access: Explicitly use properties
	2.54.5.	Nullable Types Access: shortcut syntax
	2.54.6.	Nullable Types Assignment
	2.54.7.	Null Coalescing Operator
	2.54.8.	A nullable type
	2.54.9.	Use nullable objects in expressions: result contains null, because one operand is null
	2.54.10.	Assign value to nullable int
	2.54.11.	Using ??

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