/// <summary> /// 正序下标从零开始 /// 倒序下标从一开始 /// </summary> public void Demo3() { // 正序下标从零开始 // 倒序下标从一开始 var words = new string[] { // index from start, index from end "The", // 0, ^9 "quick", // 1, ^8 "brown", // 2, ^7 "fox", // 3, ^6 "jumped", // 4, ^5 "over", // 5, ^4 "the", // 6, ^3 "lazy", // 7, ^2 "dog" // 8, ^1 }; //取最后一个元素 Console.WriteLine($"The last word is {words[^1]}");//dog //获取下标是一的元素到下标是三的元素 var quickBrownFox = words[1..4]; Console.WriteLine(quickBrownFox);//quick,brown,fox //获取倒数第二个元素到倒数第一个元素 var lazyDog = words[^2..^0]; Console.WriteLine(lazyDog);//lazy,dog //获取倒数第二个元素到结束 var lazyDog2 = words[^2..]; Console.WriteLine(lazyDog2);//lazy,dog //获取全部元素 var all = words[..]; Console.WriteLine(all); //获取开始到下标是四的元素 var firstPhrase = words[..4]; Console.WriteLine(firstPhrase);//The,quick,brown,fox //获取下标是六的元素到结束 var lastPhrase = words[6..]; Console.WriteLine(lastPhrase);//the,lazy,dog }