Tuple<T1>.IStructuralEquatable.Equals(Object, IEqualityComparer) Método
Definición
Importante
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Devuelve un valor que indica si el objeto Tuple<T1> actual es igual que el objeto especificado según el método de comparación especificado.
virtual bool System.Collections.IStructuralEquatable.Equals(System::Object ^ other, System::Collections::IEqualityComparer ^ comparer) = System::Collections::IStructuralEquatable::Equals;bool IStructuralEquatable.Equals (object other, System.Collections.IEqualityComparer comparer);abstract member System.Collections.IStructuralEquatable.Equals : obj * System.Collections.IEqualityComparer -> bool
override this.System.Collections.IStructuralEquatable.Equals : obj * System.Collections.IEqualityComparer -> boolFunction Equals (other As Object, comparer As IEqualityComparer) As Boolean Implements IStructuralEquatable.EqualsParámetros
- other
- Object
Objeto que se va a comparar con esta instancia.
- comparer
- IEqualityComparer
Un objeto que define el método que se usará para evaluar si los dos objetos son iguales.
Devoluciones
true si la instancia actual es igual que el objeto especificado; en caso contrario, false.
Implementaciones
Ejemplos
En el ejemplo siguiente se define una IEqualityComparer implementación que considera que dos valores de punto flotante son iguales entre sí (es decir, si un valor está dentro del 01 por ciento del otro).
using System;
using System.Collections;
public class Tuple1Comparer : IEqualityComparer
{
new public bool Equals(object x, object y)
{
// Check if x is a floating point type. If x is, then y is.
if (x is double | x is float)
{
// Convert to Double values.
double dblX = (double) x;
double dblY = (double) y;
if (Double.IsNaN(dblX) | Double.IsInfinity(dblX) |
Double.IsNaN(dblY) | Double.IsInfinity(dblY))
return dblX.Equals(dblY);
else
return Math.Abs(dblX - dblY) <= dblX * .0001;
}
else
{
return x.Equals(y);
}
}
public int GetHashCode(object obj)
{
return obj.GetHashCode();
}
}
public class Example
{
public static void Main()
{
var doubleTuple1 = Tuple.Create(12.3455);
var doubleTuple2 = Tuple.Create(16.8912);
var doubleTuple3 = Tuple.Create(12.3449599);
// Compare first tuple with a Tuple<double> with a different value.
TestEquality(doubleTuple1, doubleTuple2);
//Compare first tuple with a Tuple<double> with the same value.
TestEquality(doubleTuple1, doubleTuple3);
}
private static void TestEquality(Tuple<double> tuple, object obj)
{
Console.WriteLine("{0} = {1}: {2}", tuple.ToString(),
obj.ToString(),
((IStructuralEquatable)tuple).Equals(obj, new Tuple1Comparer()));
}
}
// The example displays the following output:
// (12.3455) = (16.8912): False
// (12.3455) = (12.3449599): True
open System
open System.Collections
type Tuple1Comparer() =
interface IEqualityComparer with
member _.Equals(x: obj, y: obj) =
match x with
| :? double as dblX ->
// Convert to Double values.
let dblY = y :?> double
if Double.IsNaN dblX || Double.IsInfinity dblX ||
Double.IsNaN dblY || Double.IsInfinity dblY then
dblX.Equals dblY
else
abs (dblX - dblY) <= dblX * 0.0001
| _ ->
x.Equals y
member _.GetHashCode(obj: obj) =
obj.GetHashCode()
let testEquality (tuple: Tuple<double>) (obj: obj) =
printfn $"{tuple} = {obj}: {(tuple :> IStructuralEquatable).Equals(obj, Tuple1Comparer())}"
let doubleTuple1 = Tuple.Create 12.3455
let doubleTuple2 = Tuple.Create 16.8912
let doubleTuple3 = Tuple.Create 12.3449599
// Compare first tuple with a Tuple<double> with a different value.
testEquality doubleTuple1 doubleTuple2
//Compare first tuple with a Tuple<double> with the same value.
testEquality doubleTuple1 doubleTuple3
// The example displays the following output:
// (12.3455) = (16.8912): False
// (12.3455) = (12.3449599): True
Imports System.Collections
Public Class Tuple1Comparer : Implements IEqualityComparer
Public Overloads Function Equals(x As Object, y As Object) As Boolean _
Implements IEqualityComparer.Equals
' Check if x is a floating point type. If x is, then y is.
If TypeOf x Is Double Or TypeOf x Is Single Then
' Convert to Double values.
Dim dblX As Double = CDbl(x)
Dim dblY As Double = CDbl(y)
If Double.IsNan(dblX) Or Double.IsInfinity(dblX) Or _
Double.IsNan(dblY) Or Double.IsInfinity(dblY) Then
Return dblX.Equals(dblY)
Else
Return Math.Abs(dblX - dblY) <= dblY * .0001
End If
Else
Return x.Equals(y)
End If
End Function
Public Overloads Function GetHashCode(obj As Object) As Integer _
Implements IEqualityComparer.GetHashCode
Return obj.GetHashCode()
End Function
End Class
Module Example
Public Sub Main()
Dim doubleTuple1 = Tuple.Create(12.3455)
Dim doubleTuple2 = Tuple.Create(16.8912)
Dim doubleTuple3 = Tuple.Create(12.3449599)
' Compare first tuple with a Tuple(Of Double) with a different value.
TestEquality(doubleTuple1, doubleTuple2)
' Compare first tuple with a Tuple(Of Double) with the same value.
TestEquality(doubleTuple1, doubleTuple3)
End Sub
Private Sub TestEquality(tuple As Tuple(Of Double), obj As Object)
Try
Console.WriteLine("{0} = {1}: {2}", tuple.ToString(),
obj.ToString,
DirectCAst(tuple, IStructuralEquatable).Equals(obj, New Tuple1Comparer()))
Catch e As ArgumentException
If obj.GetType.IsGenericType Then
If obj.GetType().Name = "Tuple`1" Then
Console.WriteLine("Cannot compare a Tuple(Of {0}) with a Tuple(Of {1}).",
tuple.Item1.GetType().Name, obj.Item1.GetType().Name)
Else
Console.WriteLine("Cannot compare a {0} with a {1}.", tuple.GetType().Name,
obj.GetType().Name)
End If
Else
Console.WriteLine("Cannot compare a {0} with a {1}.", tuple.GetType().Name,
obj.GetType().Name)
End If
End Try
End Sub
End Module
' The example displays the following output:
' (12.3455) = (16.8912): False
' (12.3455) = (12.3449599): True
Comentarios
Este miembro es una implementación explícita de un miembro de interfaz. Solo se puede utilizar cuando la instancia de Tuple<T1> se convierte en una interfaz IStructuralEquatable.
Solo se llama a la IEqualityComparer.Equals implementación si other no nulles y si se puede convertir correctamente (en C#) o convertir (en Visual Basic) en un Tuple<T1> objeto cuyo único componente sea del mismo tipo que la instancia actual. El método se pasa al Item1 componente de la instancia actual y al Item1 componente del Tuple<T1> objeto representado por el other parámetro .
