本文整理汇总了C#中System.Collections.Generic.EqualityComparer<T>.Default属性的典型用法代码示例。如果您正苦于以下问题：C# EqualityComparer<T>.Default属性的具体用法？C# EqualityComparer<T>.Default怎么用？C# EqualityComparer<T>.Default使用的例子？那么, 这里精选的属性代码示例或许可以为您提供帮助。您也可以进一步了解该属性所在类System.Collections.Generic.EqualityComparer<T>的用法示例。
在下文中一共展示了EqualityComparer<T>.Default属性的1个代码示例，这些例子默认根据受欢迎程度排序。您可以为喜欢或者感觉有用的代码点赞，您的评价将有助于系统推荐出更棒的C#代码示例。
示例1: Main
//引入命名空间
using System;
using System.Collections.Generic;
static class Program
{
static void Main()
{
var redBox = new Box(8, 8, 4);
var blueBox = new Box(6, 8, 4);
var greenBox = new Box(4, 8, 8);
var boxes = new[] { redBox, blueBox, greenBox };
var boxToFind = new Box(4, 8, 8);
var foundByDimension = boxes.FindFirst(boxToFind);
Console.WriteLine($"Found box {foundByDimension} by dimension.");
var foundByVolume = boxes.FindFirst(boxToFind, new BoxEqVolume());
Console.WriteLine($"Found box {foundByVolume} by volume.");
}
}
public static class CollectionExtensions
{
public static T FindFirst<T>(
this IEnumerable<T> collection, T itemToFind, IEqualityComparer<T> comparer = null)
{
comparer = comparer ?? EqualityComparer<T>.Default;
foreach (var item in collection)
{
if (comparer.Equals(item, itemToFind))
{
return item;
}
}
throw new InvalidOperationException("No matching item found.");
}
}
public class BoxEqVolume : EqualityComparer<Box>
{
public override bool Equals(Box b1, Box b2)
{
if (object.ReferenceEquals(b1, b2))
return true;
if (b1 is null || b2 is null)
return false;
return b1.Volume == b2.Volume;
}
public override int GetHashCode(Box box) => box.Volume.GetHashCode();
}
public class Box : IEquatable<Box>
{
public Box(int height, int length, int width)
{
this.Height = height;
this.Length = length;
this.Width = width;
}
public int Height { get; }
public int Length { get; }
public int Width { get; }
public int Volume => Height * Length * Width;
public bool Equals(Box other)
{
if (other is null)
return false;
return this.Height == other.Height && this.Length == other.Length
&& this.Width == other.Width;
}
public override bool Equals(object obj) => Equals(obj as Box);
public override int GetHashCode() => (Height, Length, Width).GetHashCode();
public override string ToString() => $"{Height} x {Length} x {Width}";
}输出：
*
Found box 4 x 8 x 8 by dimension.
Found box 8 x 8 x 4 by volume.