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object (C# Reference) 

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The object type is an alias for Object in the .NET Framework. In the unified type system of C#, all types, predefined and user-defined, reference types and value types, inherit directly or indirectly from Object. You can assign values of any type to variables of type object. When a variable of a value type is converted to object, it is said to be boxed. When a variable of type object is converted to a value type, it is said to be unboxed. For more information, see Boxing and Unboxing.

Example

The following sample shows how variables of type object can accept values of any data type and how variables of type object can use methods on Object from the .NET Framework.

// keyword_object.cs
using System;
class SampleClass
{
   public int i = 10;
}

class MainClass
{
   static void Main()
   {
      object a;
      a = 1;   // an example of boxing
      Console.WriteLine(a);
      Console.WriteLine(a.GetType());
      Console.WriteLine(a.ToString());

      a = new SampleClass();
      SampleClass classRef;
      classRef = (SampleClass)a;
      Console.WriteLine(classRef.i);
   }
}

Output

1
System.Int32
1
10

C# Language Specification

For more information, see the following sections in the C# Language Specification:

  • 1 Introduction

  • 4.2.2 The object type

See Also

Reference

C# Keywords
Reference Types (C# Reference)
Value Types (C# Reference)

Concepts

C# Programming Guide

Other Resources

C# Reference