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Decimal.Equals Metodo

  • Riferimento

Definizione

Spazio dei nomi:
System
Assembly:
System.Runtime.dll
Assembly:
mscorlib.dll
Assembly:
netstandard.dll

Restituisce un valore che indica se due istanze di Decimal rappresentano lo stesso valore.

Overload

Equals(Decimal, Decimal)

Restituisce un valore che indica se due istanze specificate di Decimal rappresentano lo stesso valore.
Equals(Decimal)

Restituisce un valore che indica se questa istanza e un oggetto Decimal specificato rappresentano lo stesso valore.
Equals(Object)

Restituisce un valore che indica se questa istanza e un Object specificato rappresentano lo stesso tipo e valore.

Equals(Decimal, Decimal)

Origine:
Decimal.cs
Origine:
Decimal.cs
Origine:
Decimal.cs

Restituisce un valore che indica se due istanze specificate di Decimal rappresentano lo stesso valore.

public:
 static bool Equals(System::Decimal d1, System::Decimal d2);
public static bool Equals (decimal d1, decimal d2);
static member Equals : decimal * decimal -> bool
Public Shared Function Equals (d1 As Decimal, d2 As Decimal) As Boolean

Parametri

d1
Decimal

Primo valore da confrontare.

d2
Decimal

Secondo valore da confrontare.

Restituisce

Boolean

true se d1 e d2 sono uguali; in caso contrario, false.

Esempio

Nell'esempio di codice seguente vengono confrontati diversi valori Decimal con un valore di riferimento Decimal usando il metodo Equals statico.

// Example of the Decimal::Compare and static Decimal::Equals methods.
using namespace System;
const __wchar_t * protoFmt = L"{0,-45}{1}";

// Compare Decimal parameters, and display them with the results.
void CompareDecimals( Decimal Left, Decimal Right, String^ RightText )
{
   String^ dataFmt = gcnew String( protoFmt );
   Console::WriteLine();
   Console::WriteLine( dataFmt, String::Concat( "Right: ", RightText ), Right );
   Console::WriteLine( dataFmt, "Decimal::Equals( Left, Right )", Decimal::Equals( Left, Right ) );
   Console::WriteLine( dataFmt, "Decimal::Compare( Left, Right )", Decimal::Compare( Left, Right ) );
}

int main()
{
   Console::WriteLine( "This example of the Decimal::Equals( Decimal, Decimal "
   ") and \nDecimal::Compare( Decimal, Decimal ) "
   "methods generates the \nfollowing output. It creates "
   "several different Decimal \nvalues and compares them "
   "with the following reference value.\n" );
   
   // Create a reference Decimal value.
   Decimal Left = Decimal(123.456);
   Console::WriteLine( gcnew String( protoFmt ), "Left: Decimal( 123.456 )", Left );
   
   // Create Decimal values to compare with the reference.
   CompareDecimals( Left, Decimal(1.2345600E+2), "Decimal( 1.2345600E+2 )" );
   CompareDecimals( Left, Decimal::Parse( "123.4561" ), "Decimal::Parse( \"123.4561\" )" );
   CompareDecimals( Left, Decimal::Parse( "123.4559" ), "Decimal::Parse( \"123.4559\" )" );
   CompareDecimals( Left, Decimal::Parse( "123.456000" ), "Decimal::Parse( \"123.456000\" )" );
   CompareDecimals( Left, Decimal(123456000,0,0,false,6), "Decimal( 123456000, 0, 0, false, 6 )" );
}

/*
This example of the Decimal::Equals( Decimal, Decimal ) and
Decimal::Compare( Decimal, Decimal ) methods generates the
following output. It creates several different Decimal
values and compares them with the following reference value.

Left: Decimal( 123.456 )                     123.456

Right: Decimal( 1.2345600E+2 )               123.456
Decimal::Equals( Left, Right )               True
Decimal::Compare( Left, Right )              0

Right: Decimal::Parse( "123.4561" )          123.4561
Decimal::Equals( Left, Right )               False
Decimal::Compare( Left, Right )              -1

Right: Decimal::Parse( "123.4559" )          123.4559
Decimal::Equals( Left, Right )               False
Decimal::Compare( Left, Right )              1

Right: Decimal::Parse( "123.456000" )        123.456000
Decimal::Equals( Left, Right )               True
Decimal::Compare( Left, Right )              0

Right: Decimal( 123456000, 0, 0, false, 6 )  123.456000
Decimal::Equals( Left, Right )               True
Decimal::Compare( Left, Right )              0
*/

// Example of the decimal.Compare and static decimal.Equals methods.
using System;

class DecCompareEqualsDemo
{
    const string dataFmt = "{0,-45}{1}";

    // Compare decimal parameters, and display them with the results.
    public static void CompareDecimals( decimal Left, decimal Right,
        string RightText )
    {
        Console.WriteLine( );
        Console.WriteLine( dataFmt, "Right: "+RightText, Right );
        Console.WriteLine( dataFmt, "decimal.Equals( Left, Right )",
            Decimal.Equals( Left, Right ) );
        Console.WriteLine( dataFmt, "decimal.Compare( Left, Right )",
            Decimal.Compare( Left, Right ) );
    }

    public static void Main( )
    {
        Console.WriteLine( "This example of the " +
            "decimal.Equals( decimal, decimal ) and \n" +
            "decimal.Compare( decimal, decimal ) methods " +
            "generates the \nfollowing 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( 123.456 );

        Console.WriteLine( dataFmt, "Left: decimal( 123.456 )",
            Left );

        // Create decimal values to compare with the reference.
        CompareDecimals( Left, new decimal( 1.2345600E+2 ),
            "decimal( 1.2345600E+2 )" );
        CompareDecimals( Left, 123.4561M, "123.4561M" );
        CompareDecimals( Left, 123.4559M, "123.4559M" );
        CompareDecimals( Left, 123.456000M, "123.456000M" );
        CompareDecimals( Left,
            new decimal( 123456000, 0, 0, false, 6 ),
            "decimal( 123456000, 0, 0, false, 6 )" );
    }
}

/*
This example of the decimal.Equals( decimal, decimal ) and
decimal.Compare( decimal, decimal ) methods generates the
following output. It creates several different decimal
values and compares them with the following reference value.

Left: decimal( 123.456 )                     123.456

Right: decimal( 1.2345600E+2 )               123.456
decimal.Equals( Left, Right )                True
decimal.Compare( Left, Right )               0

Right: 123.4561M                             123.4561
decimal.Equals( Left, Right )                False
decimal.Compare( Left, Right )               -1

Right: 123.4559M                             123.4559
decimal.Equals( Left, Right )                False
decimal.Compare( Left, Right )               1

Right: 123.456000M                           123.456000
decimal.Equals( Left, Right )                True
decimal.Compare( Left, Right )               0

Right: decimal( 123456000, 0, 0, false, 6 )  123.456000
decimal.Equals( Left, Right )                True
decimal.Compare( Left, Right )               0
*/

// Example of the decimal.Compare and static decimal.Equals methods.
open System

let print message obj = printfn $"%-45s{message}{obj}"

// Compare decimal parameters, and display them with the results.
let compareDecimals (left: decimal) (right: decimal) (rightText: string) =
    printfn ""
    print $"right: {rightText}" right
    print "decimal.Equals(left, right)  " (Decimal.Equals(left, right))
    print "decimal.Compare(left, right)  " (Decimal.Compare(left, right))

Console.WriteLine( "This example of the " +
    "decimal.Equals(decimal, decimal) and \n" +
    "decimal.Compare(decimal, decimal) methods " +
    "generates the \nfollowing output. It creates several " +
    "different decimal \nvalues and compares them with " +
    "the following reference value.\n" )

// Create a reference decimal value.
let left = decimal 123.456

print "left: decimal( 123.456 )" left

// Create decimal values to compare with the reference.
compareDecimals left (decimal 1.2345600E+2 ) "decimal(1.2345600E+2)"
compareDecimals left 123.4561M "123.4561M"
compareDecimals left 123.4559M "123.4559M"
compareDecimals left 123.456000M "123.456000M"
compareDecimals left (Decimal(123456000, 0, 0, false, 6uy)) "Decimal(123456000, 0, 0, false, 6)"


// This example of the decimal.Equals(decimal, decimal) and
// decimal.Compare(decimal, decimal) methods generates the
// following output. It creates several different decimal
// values and compares them with the following reference value.

// left: decimal(123.456)                       123.456

// right: decimal(1.2345600E+2)                 123.456
// decimal.Equals(left, right)                  True
// decimal.Compare(left, right)                 0

// right: 123.4561M                             123.4561
// decimal.Equals(left, right)                  False
// decimal.Compare(left, right)                 -1

// right: 123.4559M                             123.4559
// decimal.Equals(left, right)                  False
// decimal.Compare(left, right)                 1

// right: 123.456000M                           123.456000
// decimal.Equals(left, right)                  True
// decimal.Compare(left, right)                 0

// right: decimal(123456000, 0, 0, false, 6)    123.456000
// decimal.Equals(left, right)                  True
// decimal.Compare(left, right)                 0

' Example of the Decimal.Compare and static Decimal.Equals methods.
Module DecCompareEqualsDemo
    
    Const dataFmt As String = "{0,-45}{1}"

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

        Console.WriteLine( )
        Console.WriteLine( dataFmt, "Right: " & RightText, Right )
        Console.WriteLine( dataFmt, "Decimal.Equals( Left, Right )", _
            Decimal.Equals( Left, Right ) )
        Console.WriteLine( dataFmt, _
            "Decimal.Compare( Left, Right )", _
            Decimal.Compare( Left, Right ) )
    End Sub

    Sub Main( )
        Console.WriteLine( _
            "This example of the Decimal.Equals( Decimal, " & _
            "Decimal ) and " & vbCrLf & "Decimal.Compare( " & _
            "Decimal, Decimal ) 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( 123.456 )

        Console.WriteLine( dataFmt, "Left: Decimal( 123.456 )", Left )

        ' Create Decimal values to compare with the reference.
        CompareDecimals( Left, New Decimal( 1.2345600E+2 ), _
            "Decimal( 1.2345600E+2 )" )
        CompareDecimals( Left, 123.4561D, "123.4561D" )
        CompareDecimals( Left, 123.4559D, "123.4559D" )
        CompareDecimals( Left, 123.456000D, "123.456000D" )
        CompareDecimals( Left, _
            New Decimal( 123456000, 0, 0, false, 6 ), _
            "Decimal( 123456000, 0, 0, false, 6 )" )
    End Sub 
End Module 

' This example of the Decimal.Equals( Decimal, Decimal ) and
' Decimal.Compare( Decimal, Decimal ) methods generates the
' following output. It creates several different Decimal
' values and compares them with the following reference value.
' 
' Left: Decimal( 123.456 )                     123.456
' 
' Right: Decimal( 1.2345600E+2 )               123.456
' Decimal.Equals( Left, Right )                True
' Decimal.Compare( Left, Right )               0
' 
' Right: 123.4561D                             123.4561
' Decimal.Equals( Left, Right )                False
' Decimal.Compare( Left, Right )               -1
' 
' Right: 123.4559D                             123.4559
' Decimal.Equals( Left, Right )                False
' Decimal.Compare( Left, Right )               1
' 
' Right: 123.456000D                           123.456
' Decimal.Equals( Left, Right )                True
' Decimal.Compare( Left, Right )               0
' 
' Right: Decimal( 123456000, 0, 0, false, 6 )  123.456000
' Decimal.Equals( Left, Right )                True
' Decimal.Compare( Left, Right )               0

Vedi anche

Si applica a

Equals(Decimal)

Origine:
Decimal.cs
Origine:
Decimal.cs
Origine:
Decimal.cs

Restituisce un valore che indica se questa istanza e un oggetto Decimal specificato rappresentano lo stesso valore.

public:
 virtual bool Equals(System::Decimal value);
public bool Equals (decimal value);
override this.Equals : decimal -> bool
Public Function Equals (value As Decimal) As Boolean

Parametri

value
Decimal

Oggetto da confrontare con questa istanza.

Restituisce

Boolean

true se value è uguale a questa istanza; in caso contrario, false.

Implementazioni

Equals(T)

Commenti

Questo metodo implementa l'interfaccia System.IEquatable<T> ed esegue prestazioni leggermente migliori di Equals perché non è necessario convertire il parametro value in un oggetto .

Se value ha meno bit (è più piccolo) rispetto al tipo di istanza, alcuni linguaggi di programmazione eseguono una conversione implicita di ampliamento che trasforma il valore del parametro in un valore con più bit.

Si supponga, ad esempio, che il tipo di istanza sia Int32 e che il tipo di parametro sia Byte. Il compilatore Microsoft C# genera istruzioni per rappresentare il valore del parametro come oggetto Int32, quindi genera un metodo Int32.CompareTo per confrontare l'istanza di Int32 e la rappresentazione dei parametri.

Consultare la documentazione del linguaggio di programmazione per determinare se il compilatore esegue conversioni implicite di ampliamento sui tipi numerici.

Note per i chiamanti

La risoluzione dell'overload del compilatore può tenere conto di una differenza apparente nel comportamento dei due overload del metodo Equals(Object). Se viene definita una conversione implicita tra l'argomento value e un Decimal e l'argomento non viene tipizzato come Object, i compilatori possono eseguire una conversione implicita e chiamare il metodo Equals(Decimal). In caso contrario, chiamano il metodo Equals(Object), che restituisce sempre false se il relativo argomento value non è un valore Decimal. Nell'esempio seguente viene illustrata la differenza di comportamento tra i due overload del metodo. Nel caso di tutti i tipi integrali primitivi, inclusi i tipi con segno e senza segno, il primo confronto restituisce true perché il compilatore esegue automaticamente una conversione più ampia e chiama il metodo Equals(Decimal), mentre il secondo confronto restituisce false perché il compilatore chiama il metodo Equals(Object).

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 (Decimal) = 112 (Byte): False
//
//       value = short1:              True
//       112 (Decimal) = 112 (Int16): False
//
//       value = int1:                True
//       112 (Decimal) = 112 (Int32): False
//
//       value = long1:               True
//       112 (Decimal) = 112 (Int64): False
//
//       value = sbyte1:              True
//       112 (Decimal) = 112 (SByte): False
//
//       value = ushort1:              True
//       112 (Decimal) = 112 (UInt16): False
//
//       value = uint1:                True
//       112 (Decimal) = 112 (UInt32): False
//
//       value = ulong1:               True
//       112 (Decimal) = 112 (UInt64): False
//
//       value = sng1:                 False
//       112 (Decimal) = 112 (Single): False
//
//       value = dbl1:                 False
//       112 (Decimal) = 112 (Double): False

let value = 112m

let testObjectForEquality (obj: obj) =
    printfn $"{value} ({value.GetType().Name}) = {obj} ({obj.GetType().Name}): {value.Equals obj}\n"

let byte1 = 112uy
printfn $"value = byte1: {value.Equals byte1,17}"
testObjectForEquality byte1

let short1 = 112s
printfn $"value = short1: {value.Equals short1,17}"
testObjectForEquality short1

let int1 = 112
printfn $"value = int1: {value.Equals int1,19}"
testObjectForEquality int1

let long1 = 112L
printfn $"value = long1: {value.Equals long1,18}"
testObjectForEquality long1

let sbyte1 = 112y
printfn $"value = sbyte1: {value.Equals sbyte1,17}"
testObjectForEquality sbyte1

let ushort1 = 112us
printfn $"value = ushort1: {value.Equals ushort1,17}"
testObjectForEquality ushort1

let uint1 = 112u
printfn $"value = uint1: {value.Equals uint1,19}"
testObjectForEquality uint1

let ulong1 = 112uL
printfn $"value = ulong1: {value.Equals ulong1,18}"
testObjectForEquality ulong1

let sng1 = 112f
printfn $"value = sng1: {value.Equals sng1,21}"
testObjectForEquality sng1

let dbl1 = 112.
printfn $"value = dbl1: {value.Equals dbl1,21}"
testObjectForEquality dbl1


// The example displays the following output:
//       value = byte1:              True
//       112 (Decimal) = 112 (Byte): False
//
//       value = short1:              True
//       112 (Decimal) = 112 (Int16): False
//
//       value = int1:                True
//       112 (Decimal) = 112 (Int32): False
//
//       value = long1:               True
//       112 (Decimal) = 112 (Int64): False
//
//       value = sbyte1:              True
//       112 (Decimal) = 112 (SByte): False
//
//       value = ushort1:              True
//       112 (Decimal) = 112 (UInt16): False
//
//       value = uint1:                True
//       112 (Decimal) = 112 (UInt32): False
//
//       value = ulong1:               True
//       112 (Decimal) = 112 (UInt64): False
//
//       value = sng1:                 False
//       112 (Decimal) = 112 (Single): False
//
//       value = dbl1:                 False
//       112 (Decimal) = 112 (Double): False

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 (Decimal) = 112 (Byte): False
'
'       value = short1:              True
'       112 (Decimal) = 112 (Int16): False
'
'       value = int1:                True
'       112 (Decimal) = 112 (Int32): False
'
'       value = long1:               True
'       112 (Decimal) = 112 (Int64): False
'
'       value = sbyte1:              True
'       112 (Decimal) = 112 (SByte): False
'
'       value = ushort1:              True
'       112 (Decimal) = 112 (UInt16): False
'
'       value = uint1:                True
'       112 (Decimal) = 112 (UInt32): False
'
'       value = ulong1:               True
'       112 (Decimal) = 112 (UInt64): False
'
'       value = sng1:                 False
'       112 (Decimal) = 112 (Single): False
'
'       value = dbl1:                 False
'       112 (Decimal) = 112 (Double): False

Vedi anche

Si applica a

Equals(Object)

Origine:
Decimal.cs
Origine:
Decimal.cs
Origine:
Decimal.cs

Restituisce un valore che indica se questa istanza e un Object specificato rappresentano lo stesso tipo e valore.

public:
 override bool Equals(System::Object ^ value);
public override bool Equals (object value);
public override bool Equals (object? value);
override this.Equals : obj -> bool
Public Overrides Function Equals (value As Object) As Boolean

Parametri

value
Object

Oggetto da confrontare con questa istanza.

Restituisce

Boolean

true se value è un Decimal e uguale a questa istanza; in caso contrario, false.

Esempio

Nell'esempio di codice seguente vengono confrontati diversi Decimal e altri oggetti con un valore di riferimento Decimal usando il metodo Equals.

// Example of the Decimal::CompareTo and Decimal::Equals instance 
// methods.
using namespace System;

// Get the exception type name; remove the namespace prefix.
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.
void CompDecimalToObject( Decimal Left, Object^ Right, String^ RightText )
{
   Console::WriteLine( "{0,-46}{1}", String::Concat( "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 ) );
   }

}

int 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 = Decimal(987.654);
   Console::WriteLine( "{0,-46}{1}\n", "Left: Decimal( 987.654 )", Left );
   
   // Create objects to compare with the reference.
   CompDecimalToObject( Left, Decimal(9.8765400E+2), "Decimal( 9.8765400E+2 )" );
   CompDecimalToObject( Left, Decimal::Parse( "987.6541" ), "Decimal::Parse( \"987.6541\" )" );
   CompDecimalToObject( Left, Decimal::Parse( "987.6539" ), "Decimal::Parse( \"987.6539\" )" );
   CompDecimalToObject( Left, 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: Decimal::Parse( "987.6541" )          987.6541
Left.Equals( Object )                         False
Left.CompareTo( Object )                      -1

Object: Decimal::Parse( "987.6539" )          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
*/

// 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
*/

// Example of the decimal.CompareTo and decimal.Equals instance
// methods.
open System

// Get the exception type name remove the namespace prefix.
let getExceptionType (ex: exn) =
    let exceptionType = ex.GetType() |> string
    exceptionType.Substring(exceptionType.LastIndexOf '.'  + 1)

// Compare the decimal to the object parameters,
// and display the object parameters with the results.
let compDecimalToObject (left: decimal) (right: obj) (rightText: string) =
    printfn $"object: %-38s{rightText}{right}"
    printfn $"""%-46s{"left.Equals(object)"}{left.Equals right}"""       
    printf $"""%-46s{"left.CompareTo(object)"}"""

    try
        // Catch the exception if CompareTo( ) throws one.
        printfn $"{left.CompareTo right}\n"
    with ex ->
        printfn $"{getExceptionType ex}\n"

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.
let left = decimal 987.654

printfn $"""{"Left: decimal(987.654)",-46}{left}\n"""

// Create objects to compare with the reference.
compDecimalToObject left (decimal 9.8765400E+2 ) "decimal(9.8765400E+2)"
compDecimalToObject left 987.6541M "987.6541D"
compDecimalToObject left 987.6539M "987.6539D"
compDecimalToObject left (Decimal(987654000, 0, 0, false, 6uy)) "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

' Example of the Decimal.CompareTo and Decimal.Equals instance methods.
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

Note per i chiamanti

La risoluzione dell'overload del compilatore può tenere conto di una differenza apparente nel comportamento dei due overload del metodo Equals(Object). Se viene definita una conversione implicita tra l'argomento value e un Decimal e l'argomento non viene tipizzato come Object, i compilatori possono eseguire una conversione implicita e chiamare il metodo Equals(Decimal). In caso contrario, chiamano il metodo Equals(Object), che restituisce sempre false se il relativo argomento value non è un valore Decimal. Nell'esempio seguente viene illustrata la differenza di comportamento tra i due overload del metodo. Nel caso di tutti i tipi integrali primitivi, inclusi i tipi con segno e senza segno, il primo confronto restituisce true perché il compilatore esegue automaticamente una conversione più ampia e chiama il metodo Equals(Decimal), mentre il secondo confronto restituisce false perché il compilatore chiama il metodo Equals(Object).

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 (Decimal) = 112 (Byte): False
//
//       value = short1:              True
//       112 (Decimal) = 112 (Int16): False
//
//       value = int1:                True
//       112 (Decimal) = 112 (Int32): False
//
//       value = long1:               True
//       112 (Decimal) = 112 (Int64): False
//
//       value = sbyte1:              True
//       112 (Decimal) = 112 (SByte): False
//
//       value = ushort1:              True
//       112 (Decimal) = 112 (UInt16): False
//
//       value = uint1:                True
//       112 (Decimal) = 112 (UInt32): False
//
//       value = ulong1:               True
//       112 (Decimal) = 112 (UInt64): False
//
//       value = sng1:                 False
//       112 (Decimal) = 112 (Single): False
//
//       value = dbl1:                 False
//       112 (Decimal) = 112 (Double): False

let value = 112m

let testObjectForEquality (obj: obj) =
    printfn $"{value} ({value.GetType().Name}) = {obj} ({obj.GetType().Name}): {value.Equals obj}\n"

let byte1 = 112uy
printfn $"value = byte1: {value.Equals byte1,17}"
testObjectForEquality byte1

let short1 = 112s
printfn $"value = short1: {value.Equals short1,17}"
testObjectForEquality short1

let int1 = 112
printfn $"value = int1: {value.Equals int1,19}"
testObjectForEquality int1

let long1 = 112L
printfn $"value = long1: {value.Equals long1,18}"
testObjectForEquality long1

let sbyte1 = 112y
printfn $"value = sbyte1: {value.Equals sbyte1,17}"
testObjectForEquality sbyte1

let ushort1 = 112us
printfn $"value = ushort1: {value.Equals ushort1,17}"
testObjectForEquality ushort1

let uint1 = 112u
printfn $"value = uint1: {value.Equals uint1,19}"
testObjectForEquality uint1

let ulong1 = 112uL
printfn $"value = ulong1: {value.Equals ulong1,18}"
testObjectForEquality ulong1

let sng1 = 112f
printfn $"value = sng1: {value.Equals sng1,21}"
testObjectForEquality sng1

let dbl1 = 112.
printfn $"value = dbl1: {value.Equals dbl1,21}"
testObjectForEquality dbl1


// The example displays the following output:
//       value = byte1:              True
//       112 (Decimal) = 112 (Byte): False
//
//       value = short1:              True
//       112 (Decimal) = 112 (Int16): False
//
//       value = int1:                True
//       112 (Decimal) = 112 (Int32): False
//
//       value = long1:               True
//       112 (Decimal) = 112 (Int64): False
//
//       value = sbyte1:              True
//       112 (Decimal) = 112 (SByte): False
//
//       value = ushort1:              True
//       112 (Decimal) = 112 (UInt16): False
//
//       value = uint1:                True
//       112 (Decimal) = 112 (UInt32): False
//
//       value = ulong1:               True
//       112 (Decimal) = 112 (UInt64): False
//
//       value = sng1:                 False
//       112 (Decimal) = 112 (Single): False
//
//       value = dbl1:                 False
//       112 (Decimal) = 112 (Double): False

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 (Decimal) = 112 (Byte): False
'
'       value = short1:              True
'       112 (Decimal) = 112 (Int16): False
'
'       value = int1:                True
'       112 (Decimal) = 112 (Int32): False
'
'       value = long1:               True
'       112 (Decimal) = 112 (Int64): False
'
'       value = sbyte1:              True
'       112 (Decimal) = 112 (SByte): False
'
'       value = ushort1:              True
'       112 (Decimal) = 112 (UInt16): False
'
'       value = uint1:                True
'       112 (Decimal) = 112 (UInt32): False
'
'       value = ulong1:               True
'       112 (Decimal) = 112 (UInt64): False
'
'       value = sng1:                 False
'       112 (Decimal) = 112 (Single): False
'
'       value = dbl1:                 False
'       112 (Decimal) = 112 (Double): False

Vedi anche

Si applica a