A nullable type : Nullable « Data Type « C# / CSharp Tutorial






  1. C# / CSharp Tutorial
  2. Data Type
  3. Nullable
using System; 
 
class MainClass{ 
  public static void Main() { 
    int? count = null; 
 
    if(count.HasValue) 
      Console.WriteLine("count has this value: " + count.Value); 
    else  
      Console.WriteLine("count has no value"); 
 
    count = 100; 
 
    if(count.HasValue) 
      Console.WriteLine("count has this value: " + count.Value); 
    else  
      Console.WriteLine("count has no value");     
  } 
}

count has no value
count has this value: 100




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 ??