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Decimal.Equals Method (Object)

Returns a value indicating whether this instance and a specified Object represent the same type and value.

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

'Declaration
Public Overrides Function Equals ( _
	value As Object _
) As Boolean

Parameters

value
Type: System.Object

The object to compare with this instance.

Return Value

Type: System.Boolean
true if value is a Decimal and equal to this instance; otherwise, false.

Notes to Callers

Compiler overload resolution may account for an apparent difference in the behavior of the two Equals method overloads. If an implicit conversion between the obj argument and a Decimal is defined and the argument is not typed as an Object, compilers may perform an implicit conversion and call the Equals(Decimal) method. Otherwise, they call the Equals(Object) method, which always returns false if its obj argument is not a Decimal value. The following example illustrates the difference in behavior between the two method overloads. In the case of all primitive integral types, including both signed and unsigned types, the first comparison returns true because the compiler automatically performs a widening conversion and calls the Equals(Decimal) method, whereas the second comparison returns false because the compiler calls the Equals(Object) method.

Module Example
   Dim value As Decimal = 112d

   Public Sub Main()
      Dim byte1 As Byte = 112
      Console.WriteLine("value = byte1: {0,17}", value.Equals(byte1))
      TestObjectForEquality(byte1)

      Dim short1 As Short = 112
      Console.WriteLine("value = short1: {0,17}", value.Equals(short1))
      TestObjectForEquality(short1)

      Dim int1 As Integer = 112
      Console.WriteLine("value = int1: {0,19}", value.Equals(int1))
      TestObjectForEquality(int1)

      Dim long1 As Long = 112
      Console.WriteLine("value = long1: {0,18}", value.Equals(long1))
      TestObjectForEquality(long1)

      Dim sbyte1 As SByte = 112
      Console.WriteLine("value = sbyte1: {0,17}", value.Equals(sbyte1))
      TestObjectForEquality(sbyte1)

      Dim ushort1 As UShort = 112
      Console.WriteLine("value = ushort1: {0,17}", value.Equals(ushort1))
      TestObjectForEquality(ushort1)

      Dim uint1 As UInteger = 112
      Console.WriteLine("value = uint1: {0,19}", value.Equals(uint1))
      TestObjectForEquality(uint1)

      Dim ulong1 As ULong = 112
      Console.WriteLine("value = ulong1: {0,18}", value.Equals(ulong1))
      TestObjectForEquality(ulong1)

      Dim sng1 As Single = 112
      Console.WriteLine("value = sng1: {0,21}", value.Equals(sng1))
      TestObjectForEquality(sng1)

      Dim dbl1 As Double = 112
      Console.WriteLine("value = dbl1: {0,21}", value.Equals(dbl1))
      TestObjectForEquality(dbl1)
   End Sub 

   Private Sub TestObjectForEquality(obj As Object)
      Console.WriteLine("{0} ({1}) = {2} ({3}): {4}",
                        value, value.GetType().Name,
                        obj, obj.GetType().Name,
                        value.Equals(obj))
      Console.WriteLine()
   End Sub 
End Module 
' The example displays the following output: 
'       value = byte1:             True 
'       112 (Double) = 112 (Byte): False 

'       value = short1:             True 
'       112 (Double) = 112 (Int16): False 

'       value = int1:               True 
'       112 (Double) = 112 (Int32): False 

'       value = long1:              True 
'       112 (Double) = 112 (Int64): False 

'       value = sbyte1:             True 
'       112 (Double) = 112 (SByte): False 

'       value = ushort1:             True 
'       112 (Double) = 112 (UInt16): False 

'       value = uint1:               True 
'       112 (Double) = 112 (UInt32): False 

'       value = ulong1:              True 
'       112 (Double) = 112 (UInt64): False 

'       value = dec1:                 True 
'       112 (Double) = 112 (Decimal): False 

'       value = sng1:                True 
'       112 (Double) = 112 (Single): False

The following code example compares several Decimal and other objects to a reference Decimal value using the Equals method.

' Example of the Decimal.CompareTo and Decimal.Equals instance methods. 
Imports System
Imports Microsoft.VisualBasic

Module DecCompToEqualsObjDemo

    ' Get the exception type name; remove the namespace prefix. 
    Function GetExceptionType( ex As Exception ) As String 

        Dim exceptionType   As String = ex.GetType( ).ToString( )
        Return exceptionType.Substring( _
            exceptionType.LastIndexOf( "."c ) + 1 )
    End Function 

    ' Compare the Decimal to the Object parameters,  
    ' and display the Object parameters with the results. 
    Sub CompDecimalToObject( Left as Decimal, Right as Object, _
        RightText as String )

        Console.WriteLine( "{0,-46}{1}", "Object: " & RightText, _
            Right )
        Console.WriteLine( "{0,-46}{1}", "Left.Equals( Object )", _
            Left.Equals( Right ) )
        Console.Write( "{0,-46}", "Left.CompareTo( Object )" )

        ' Catch the exception if CompareTo( ) throws one. 
        Try
            Console.WriteLine( "{0}" & vbCrLf, _
                Left.CompareTo( Right ) )
        Catch ex As Exception
            Console.WriteLine( "{0}" & vbCrLf, _
                GetExceptionType( ex ) )
        End Try 
    End Sub 

    Sub Main( )
        Console.WriteLine( _
            "This example of the Decimal.Equals( Object ) " & _
            "and " & vbCrLf & "Decimal.CompareTo( Object ) " & _
            "methods generates the " & vbCrLf & _
            "following output. It creates several different " & _
            "Decimal " & vbCrLf & "values and compares them " & _
            "with the following reference value." & vbCrLf )

        ' Create a reference Decimal value. 
        Dim Left as New Decimal( 987.654 )

        Console.WriteLine( "{0,-46}{1}" & vbCrLf, _
            "Left: Decimal( 987.654 )", Left )

        ' Create objects to compare with the reference.
        CompDecimalToObject( Left, New Decimal( 9.8765400E+2 ), _
            "Decimal( 9.8765400E+2 )" )
        CompDecimalToObject( Left, 987.6541D, "987.6541D" )
        CompDecimalToObject( Left, 987.6539D, "987.6539D" )
        CompDecimalToObject( Left, _
            New Decimal( 987654000, 0, 0, false, 6 ), _
            "Decimal( 987654000, 0, 0, false, 6 )" )
        CompDecimalToObject( Left, 9.8765400E+2, _
            "Double 9.8765400E+2" )
        CompDecimalToObject( Left, "987.654", _
            "String ""987.654""" )
    End Sub 
End Module  

' This example of the Decimal.Equals( Object ) and 
' Decimal.CompareTo( Object ) methods generates the 
' following output. It creates several different Decimal 
' values and compares them with the following reference value. 
'  
' Left: Decimal( 987.654 )                      987.654 
'  
' Object: Decimal( 9.8765400E+2 )               987.654 
' Left.Equals( Object )                         True 
' Left.CompareTo( Object )                      0 
'  
' Object: 987.6541D                             987.6541 
' Left.Equals( Object )                         False 
' Left.CompareTo( Object )                      -1 
'  
' Object: 987.6539D                             987.6539 
' Left.Equals( Object )                         False 
' Left.CompareTo( Object )                      1 
'  
' Object: Decimal( 987654000, 0, 0, false, 6 )  987.654000 
' Left.Equals( Object )                         True 
' Left.CompareTo( Object )                      0 
'  
' Object: Double 9.8765400E+2                   987.654 
' Left.Equals( Object )                         False 
' Left.CompareTo( Object )                      ArgumentException 
'  
' Object: String "987.654"                      987.654 
' Left.Equals( Object )                         False 
' Left.CompareTo( Object )                      ArgumentException

.NET Framework

Supported in: 4.6, 4.5, 4, 3.5, 3.0, 2.0, 1.1

.NET Framework Client Profile

Supported in: 4, 3.5 SP1

XNA Framework

Supported in: 3.0, 2.0, 1.0

Portable Class Library

Supported in: Portable Class Library

Supported in: Windows Phone 8.1

Supported in: Windows Phone Silverlight 8.1

Supported in: Windows Phone Silverlight 8
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