.Net2.0的集合操作 --- What i know?
.Net2.0中提供的Array类
namespace System {
public abstract class Array {
public static TOutput[] ConvertAll<TInput, TOutput>(TInput[] input, Converter<TInput, TOutput> cc);
public static bool Exists<T>(T[] array, Predicate<T> match);
public static T Find<T>(T[] array, Predicate<T> match);
public static T FindLast<T>(T[] array, Predicate<T> match);
public static T[] FindAll<T>(T[] array, Predicate<T> match);
public static int FindIndex<T>(T[] array, Predicate<T> match);
public static int FindLastIndex<T>(T[] array, Predicate<T> match);
public static void ForEach<T>(T[] array, Action<T> action);
public static void Sort<T>(T[] array, Comparison<T> comparer);
public static bool TrueForAll<T>(T[] array, Predicate<T> match);
}
}
public abstract class Array {
public static TOutput[] ConvertAll<TInput, TOutput>(TInput[] input, Converter<TInput, TOutput> cc);
public static bool Exists<T>(T[] array, Predicate<T> match);
public static T Find<T>(T[] array, Predicate<T> match);
public static T FindLast<T>(T[] array, Predicate<T> match);
public static T[] FindAll<T>(T[] array, Predicate<T> match);
public static int FindIndex<T>(T[] array, Predicate<T> match);
public static int FindLastIndex<T>(T[] array, Predicate<T> match);
public static void ForEach<T>(T[] array, Action<T> action);
public static void Sort<T>(T[] array, Comparison<T> comparer);
public static bool TrueForAll<T>(T[] array, Predicate<T> match);
}
}
以上的集合操作使用到了下面的一些预先定义好的代理.(从他们的名字,你就可以明白他们是干什么的)
namespace System {
public delegate void Action<T>(T item);
public delegate int Comparer<T>(T first, T second); // result works like strcmp
public delegate TOutput Converter<TInput, TOutput>(TInput input);
public delegate bool Predicate<T>(T item);
}
public delegate void Action<T>(T item);
public delegate int Comparer<T>(T first, T second); // result works like strcmp
public delegate TOutput Converter<TInput, TOutput>(TInput input);
public delegate bool Predicate<T>(T item);
}
下面是一些例子
int[] list = { 1, 2, 3, 4, 5, 6, 7, 8, 9, 10 };
int lastOdd = Array.FindLast(list, delegate(int n) { return n % 2 == 1; });
// lastOdd is 9
int[] evens = Array.FindAll(list, delegate(int n) { return n % 2 == 0; });
// evens contains { 2, 4, 6, 8, 10 }
bool hasMultipleOfSeven = Array.Exists(evens, delegate(int n) { return n % 7 == 0; });
// hasMultipleOfSeven is false
Array.Sort(evens, delegate(int a, int b) { return b - a; });
// evens is now { 10, 8, 6, 4, 2 } , you can define the sort algorithm by yourself
string[] s = Array.ConvertAll<int, string>(evens, delegate(int n) { return "#" + n.ToString(); });
// s is { "#10", "#8", "#6", "#4", "#2" } this will be cool if the compiler could do the inferencing for ConvertAll
int lastOdd = Array.FindLast(list, delegate(int n) { return n % 2 == 1; });
// lastOdd is 9
int[] evens = Array.FindAll(list, delegate(int n) { return n % 2 == 0; });
// evens contains { 2, 4, 6, 8, 10 }
bool hasMultipleOfSeven = Array.Exists(evens, delegate(int n) { return n % 7 == 0; });
// hasMultipleOfSeven is false
Array.Sort(evens, delegate(int a, int b) { return b - a; });
// evens is now { 10, 8, 6, 4, 2 } , you can define the sort algorithm by yourself
string[] s = Array.ConvertAll<int, string>(evens, delegate(int n) { return "#" + n.ToString(); });
// s is { "#10", "#8", "#6", "#4", "#2" } this will be cool if the compiler could do the inferencing for ConvertAll
pretty easy? isn't it? see much more here.