Export (0) Print
Expand All

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)

public override bool Equals(
	Object value
)

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.

using System;

public class Example
{
   static decimal value = 112m;

   public static void Main()
   {
      byte byte1= 112;
      Console.WriteLine("value = byte1: {0,17}", value.Equals(byte1));
      TestObjectForEquality(byte1);

      short short1 = 112;
      Console.WriteLine("value = short1: {0,17}", value.Equals(short1));
      TestObjectForEquality(short1);

      int int1 = 112;
      Console.WriteLine("value = int1: {0,19}", value.Equals(int1));
      TestObjectForEquality(int1);

      long long1 = 112;
      Console.WriteLine("value = long1: {0,18}", value.Equals(long1));
      TestObjectForEquality(long1);

      sbyte sbyte1 = 112;
      Console.WriteLine("value = sbyte1: {0,17}", value.Equals(sbyte1));
      TestObjectForEquality(sbyte1);

      ushort ushort1 = 112;
      Console.WriteLine("value = ushort1: {0,17}", value.Equals(ushort1));
      TestObjectForEquality(ushort1);

      uint uint1 = 112;
      Console.WriteLine("value = uint1: {0,19}", value.Equals(uint1));
      TestObjectForEquality(uint1);

      ulong ulong1 = 112;
      Console.WriteLine("value = ulong1: {0,18}", value.Equals(ulong1));
      TestObjectForEquality(ulong1);

      float sng1 = 112;
      Console.WriteLine("value = sng1: {0,21}", value.Equals(sng1));
      TestObjectForEquality(sng1);

      double dbl1 = 112;
      Console.WriteLine("value = dbl1: {0,21}", value.Equals(dbl1));
      TestObjectForEquality(dbl1);
   }

   private static void TestObjectForEquality(Object obj)
   {
      Console.WriteLine("{0} ({1}) = {2} ({3}): {4}\n",
                        value, value.GetType().Name,
                        obj, obj.GetType().Name,
                        value.Equals(obj));
   }
}
// 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:                 False 
//       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. 
using System;

class DecCompToEqualsObjDemo
{
    // Get the exception type name; remove the namespace prefix. 
    public static string GetExceptionType( Exception ex )
    {
        string exceptionType = ex.GetType( ).ToString( );
        return exceptionType.Substring( 
            exceptionType.LastIndexOf( '.' ) + 1 );
    }

    // Compare the decimal to the object parameters,  
    // and display the object parameters with the results. 
    public static void CompDecimalToObject( decimal Left, 
        object Right, string RightText )
    {

        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 )" );

        try
        {
            // Catch the exception if CompareTo( ) throws one.
            Console.WriteLine( "{0}\n", Left.CompareTo( Right ) );
        }
        catch( Exception ex )
        {
            Console.WriteLine( "{0}\n", GetExceptionType( ex ) );
        }
    }

    public static void Main( )
    {
        Console.WriteLine( 
            "This example of the decimal.Equals( object ) and \n" +
            "decimal.CompareTo( object ) methods generates the \n" +
            "following output. It creates several different " +
            "decimal \nvalues and compares them with the following " +
            "reference value.\n" );

        // Create a reference decimal value. 
        decimal Left = new decimal( 987.654 );

        Console.WriteLine( "{0,-46}{1}\n", 
            "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, 987.6541M, "987.6541D" );
        CompDecimalToObject( Left, 987.6539M, "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\"" );
    }
}

/*
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
Show:
© 2015 Microsoft