var myarr = new string[] { "10", "20", "30", "40", "50", "60", "70", "80", "90", "100" };
//提取数组myarr的前3个元素
var reult = myarr[0..3];
//使用linq提取
var result = myarr.Skip(0).Take(3);
--------输出结果：10/20/30--------

var myarr = new string[] { "10", "20", "30", "40", "50", "60", "70", "80", "90", "100" };
//提取myarr中倒数第二个元素和倒数第三个元素
var result = myarr[^3..^1];
//使用linq提取
var result = myarr.Skip(myarr.length-3).Take(2);
--------输出结果：80/90--------

var myarr = new string[] { "10", "20", "30", "40", "50", "60", "70", "80", "90", "100" };
//提取myarr中索引index=4、5、6的3个元素
var result = myarr[4..7];
//使用linq提取
var result = myarr.Skip(4).Take(3);
--------输出结果：50/60/70--------

var myarr = new string[] { "10", "20", "30", "40", "50", "60", "70", "80", "90", "100" };
//提取myarr的最后3个元素
var result = myarr[^3..];
//使用linq提取
var result = myarr.Skip(myarr.length-3);
--------输出结果：80/90/100--------