Tuple<T1,T2,T3,T4,T5,T6>.IStructuralEquatable.Equals 方法

參考

定義

命名空間:: System

組件:: System.Runtime.dll

組件:: mscorlib.dll

組件:: netstandard.dll

重要

部分資訊涉及發行前產品，在發行之前可能會有大幅修改。 Microsoft 對此處提供的資訊，不做任何明確或隱含的瑕疵擔保。

傳回值，這個值表示依據指定的比較方法，目前的 Tuple<T1,T2,T3,T4,T5,T6> 物件是否等於指定的物件。

 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 -> bool

Function Equals (other As Object, comparer As IEqualityComparer) As Boolean Implements IStructuralEquatable.Equals

參數

other: Object

與這個執行個體相互比較的物件。

comparer: IEqualityComparer

物件，定義要用來評估這兩個物件是否相等的方法。

傳回

Boolean

如果目前的執行個體和指定的物件相等，則為 true，否則為 false。

實作

Equals(Object, IEqualityComparer)

範例

下列範例會定義類別 RateComparer ，以執行相等的自訂測試。如果傳遞給其 IStructuralEquatable.Equals 方法的值的類型 Single 為或 Double ，則方法只會使用三個小數位數來測試是否相等。否則，它只會呼叫 x 參數的 Equals 方法。此範例會使用此 IEqualityComparer 實作來判斷四 Tuple<T1,T2,T3,T4,T5,T6> 個物件是否包含 1960 到 2000 之間母體擴展變更率的資料是否相等。

using System;
using System.Collections;

public class RateComparer<T1, T2, T3, T4, T5, T6> : IEqualityComparer
{
   private int argument = 0;

   public new bool Equals(object x, object y) 
   {
      argument++;
      if (argument == 1) return true;

      double fx, fy; 
      if (x is Double || x is Single)
      {
            fx = (double) x;
            fy = (double) y;
            return Math.Round(fx * 1000).Equals(Math.Round(fy * 1000));
      }
      else
      {
         return x.Equals(y);
      }
   }
   
   public int GetHashCode(object obj)
   {
      if (obj is Single || obj is Double)
         return Math.Round(((double) obj) * 1000).GetHashCode();
      else
         return obj.GetHashCode();
   }                
}

public class Example
{
   public static void Main()
   {
      var rate1 = Tuple.Create("New York", .014505, -.1042733, 
                               .0354833, .093644, .0290792);
      var rate2 = Tuple.Create("Unknown City", .014505, -.1042733, 
                               .0354833, .093644, .0290792);
      var rate3 = Tuple.Create("Unknown City", .014505, -.1042733, 
                               .0354833, .093644, .029079);
      var rate4 = Tuple.Create("San Francisco", -.0332858, -.0512803, 
                               .0662544, .0728964, .0491912);
      IStructuralEquatable eq = rate1;
      // Compare first tuple with remaining two tuples.
      Console.WriteLine("{0} = ", rate1.ToString());
      Console.WriteLine("   {0} : {1}", rate2, 
                        eq.Equals(rate2, new RateComparer<string, double, double, double, double, double>()));
      Console.WriteLine("   {0} : {1}", rate3, 
                        eq.Equals(rate3, new RateComparer<string, double, double, double, double, double>()));
      Console.WriteLine("   {0} : {1}", rate4, 
                        eq.Equals(rate4, new RateComparer<string, double, double, double, double, double>()));
   }
}
// The example displays the following output:
//    (New York, 0.014505, -0.1042733, 0.0354833, 0.093644, 0.0290792) =
//       (Unknown City, 0.014505, -0.1042733, 0.0354833, 0.093644, 0.0290792) : True
//       (Unknown City, 0.014505, -0.1042733, 0.0354833, 0.093644, 0.029079) : True
//       (San Francisco, -0.0332858, -0.0512803, 0.0662544, 0.0728964, 0.0491912) : False

open System
open System.Collections

type RateComparer<'T1, 'T2, 'T3, 'T4, 'T5, 'T6>() =
    let mutable argument = 0

    interface IEqualityComparer with
        member _.Equals(x, y) = 
            argument <- argument + 1
            if argument = 1 then true
            else
                match x with
                | :? double as fx ->
                    let fy = y :?> double
                    Math.Round(fx * 1000.).Equals(Math.Round(fy * 1000.))
                | _ ->
                    x.Equals y
        
        member _.GetHashCode(obj) =
            if obj :? Single || obj :? Double then
                Math.Round((obj :?> double) * 1000.).GetHashCode()
            else
                obj.GetHashCode()

let rate1 = Tuple.Create("New York", 0.014505, -0.1042733, 0.0354833, 0.093644, 0.0290792)
let rate2 = Tuple.Create("Unknown City", 0.014505, -0.1042733, 0.0354833, 0.093644, 0.0290792)
let rate3 = Tuple.Create("Unknown City", 0.014505, -0.1042733, 0.0354833, 0.093644, 0.029079)
let rate4 = Tuple.Create("San Francisco", -0.0332858, -0.0512803, 0.0662544, 0.0728964, 0.0491912)
let eq: IStructuralEquatable = rate1
// Compare first tuple with remaining two tuples.
printfn $"{rate1} = "
printfn $"   {rate2} : {eq.Equals(rate2, RateComparer<string, double, double, double, double, double>())}"
printfn $"   {rate3} : {eq.Equals(rate3, RateComparer<string, double, double, double, double, double>())}"
printfn $"   {rate4} : {eq.Equals(rate4, RateComparer<string, double, double, double, double, double>())}"
// The example displays the following output:
//    (New York, 0.014505, -0.1042733, 0.0354833, 0.093644, 0.0290792) =
//       (Unknown City, 0.014505, -0.1042733, 0.0354833, 0.093644, 0.0290792) : True
//       (Unknown City, 0.014505, -0.1042733, 0.0354833, 0.093644, 0.029079) : True
//       (San Francisco, -0.0332858, -0.0512803, 0.0662544, 0.0728964, 0.0491912) : False

Imports System.Collections

Public Class RateComparer(Of T1, T2, T3, T4, T5, T6) : Implements IEqualityComparer
   Private argument As Integer = 0

   Public Overloads Function Equals(x As Object, y As Object) As Boolean _
                   Implements IEqualityComparer.Equals
      argument += 1
      If argument = 1 Then
         Return True
      Else
         Dim fx, fy As Double
         If typeof x Is Double Or typeof x Is Single Then
            fx = CDbl(x)
            fy = CDbl(y)
            Return Math.Round(fx * 1000).Equals(Math.Round(fy * 1000))
         Else
            Return x.Equals(y)
         End If
      End If   
   End Function
   
   Public Overloads Function GetHashCode(obj As Object) As Integer _
                    Implements IEqualityComparer.GetHashCode
      If TypeOf(obj) Is Single Or TypeOf(obj) Is Double Then
         Return Math.Round(CDbl(obj) * 1000).GetHashCode()
      Else
         Return obj.GetHashCode()
      End If
   End Function                
End Class

Module Example
   Public Sub Main()
      Dim rate1 = Tuple.Create("New York", .014505, -.1042733, 
                               .0354833, .093644, .0290792)
      Dim rate2 = Tuple.Create("Unknown City", .014505, -.1042733, 
                               .0354833, .093644, .0290792)
      Dim rate3 = Tuple.Create("Unknown City", .014505, -.1042733, 
                               .0354833, .093644, .029079)
      Dim rate4 = Tuple.Create("San Francisco", -.0332858, -.0512803, 
                               .0662544, .0728964, .0491912)
      Dim eq As IStructuralEquatable = rate1
      ' Compare first tuple with remaining two tuples.
      Console.WriteLine("{0} = ", rate1.ToString())
      Console.WriteLine("   {0} : {1}", rate2, 
                        eq.Equals(rate2, New RateComparer(Of String, Double, Double, Double, Double, Double)()))
      Console.WriteLine("   {0} : {1}", rate3, 
                        eq.Equals(rate3, New RateComparer(Of String, Double, Double, Double, Double, Double)()))
      Console.WriteLine("   {0} : {1}", rate4, 
                        eq.Equals(rate4, New RateComparer(Of String, Double, Double, Double, Double, Double)()))
   End Sub
End Module
' The example displays the following output:
'    (New York, 0.014505, -0.1042733, 0.0354833, 0.093644, 0.0290792) =
'       (Unknown City, 0.014505, -0.1042733, 0.0354833, 0.093644, 0.0290792) : True
'       (Unknown City, 0.014505, -0.1042733, 0.0354833, 0.093644, 0.029079) : True
'       (San Francisco, -0.0332858, -0.0512803, 0.0662544, 0.0728964, 0.0491912) : False

備註

這個成員是明確介面成員實作，只有在 Tuple<T1,T2,T3,T4,T5,T6> 執行個體轉換成 IStructuralEquatable 介面時，才能使用這個成員。

只有在不是 null 時 other ，才會呼叫實 IEqualityComparer.Equals 作，如果它可以在 C#) 中成功轉換 ( (Tuple<T1,T2,T3,T4,T5,T6> ，或Visual Basic) 轉換成元件與目前實例類型相同的物件，方法 IStructuralEquatable.Equals(Object, IEqualityComparer) 會先傳遞 Item1 要與實作比較 IEqualityComparer.Equals 的物件 Tuple<T1,T2,T3,T4,T5,T6> 值。如果這個方法呼叫傳 true 回，則會再次呼叫方法，並傳遞 Item2 兩 Tuple<T1,T2,T3,T4,T5,T6> 個物件的值。這會繼續，直到方法呼叫在比較一組 Item 特定值時傳回 false ，或兩 Item6 個值會傳遞至方法。

適用於

Tuple<T1,T2,T3,T4,T5,T6>.IStructuralEquatable.Equals 方法

定義

參數

傳回

實作

範例

備註

適用於

其他資源