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ValueType.Equals Method

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Indicates whether this instance and a specified object are equal.

Namespace:  System
Assembly:  mscorlib (in mscorlib.dll)

Syntax

'Declaration
Public Overrides Function Equals ( _
    obj As Object _
) As Boolean
public override bool Equals(
    Object obj
)

Parameters

Return Value

Type: System.Boolean
true if obj and this instance are the same type and represent the same value; otherwise, false.

Remarks

The default implementation of the Equals method uses reflection to compare the corresponding fields of obj and this instance. Override the Equals method for a particular type to improve the performance of the method and more closely represent the concept of equality for the type.

Examples

The following example demonstrates how the Equals method can be overridden by a derived value type.

Public Structure Complex
   Private m_Re As Double
   Private m_Im As Double

   Public Overloads Function Equals(ByVal ob As Object) As Boolean
      If TypeOf ob Is Complex Then
         Dim c As Complex = CType(ob, Complex)
         Return m_Re = c.m_Re And m_Im = c.m_Im
      Else
         Return False
      End If
   End Function


   Public Overloads Function GetHashCode() As Integer
      Return m_Re.GetHashCode() ^ m_Im.GetHashCode()
   End Function

End Structure
public struct Complex
{
   public double m_Re;
   public double m_Im;

   public override bool Equals(object ob)
   {
      if (ob is Complex)
      {
         Complex c = (Complex)ob;
         return m_Re == c.m_Re && m_Im == c.m_Im;
      }
      else
      {
         return false;
      }
   }

   public override int GetHashCode()
   {
      return m_Re.GetHashCode() ^ m_Im.GetHashCode();
   }
}

Version Information

Silverlight

Supported in: 5, 4, 3

Silverlight for Windows Phone

Supported in: Windows Phone OS 7.1, Windows Phone OS 7.0

XNA Framework

Supported in: Xbox 360, Windows Phone OS 7.0

Platforms

For a list of the operating systems and browsers that are supported by Silverlight, see Supported Operating Systems and Browsers.

See Also

Reference