共用方式為


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

定義

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

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 nullother ,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 Item2Tuple<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