索引结构在C＃8.0中引入。它表示可用于索引集合或序列的类型，并且可以从头开始或从头开始。您可以在Index结构提供的FromStart(Int32)Method()的帮助下创建起始索引。此方法从给定集合或序列的开头在指定位置返回一个索引。
句法：
public static Index FromStart(int value);范例1：
// C# program to illustrate the
// concept of the FromStart() method
using System;
namespace example {
class GFG {
// Main Method
static void Main(string[] args)
{
// Creating start index
// Using FromStart() method
var in1 = Index.FromStart(2);
var in2 = Index.FromStart(1);
var in3 = Index.FromStart(0);
var in4 = Index.FromStart(6);
// Displaying index value
Console.WriteLine("Index position is : {0} ", in1);
Console.WriteLine("Index position is : {0} ", in2);
Console.WriteLine("Index position is : {0} ", in3);
Console.WriteLine("Index position is : {0} ", in4);
}
}
}
输出：
Index position is : 2
Index position is : 1
Index position is : 0
Index position is : 6
范例2：
// C# program to illustrate the
// concept of the FromStart() method
using System;
namespace example {
class GFG {
// Main Method
static void Main(string[] args)
{
// Creating and initializing an array
string[] greetings = new string[] {"Hello", "Hola", "Namaste",
"Bonjour", "Ohayo", "Ahnyounghaseyo"};
// Creating start index
// Using FromStart() method
var index_1 = Index.FromStart(0);
var index_2 = Index.FromStart(1);
var index_3 = Index.FromStart(4);
var index_4 = Index.FromStart(5);
// Displaying index and their values
Console.WriteLine("Index: {0} Value: {1}",
index_1, greetings[index_1]);
Console.WriteLine("Index: {0} Value: {1}",
index_2, greetings[index_2]);
Console.WriteLine("Index: {0} Value: {1}",
index_3, greetings[index_3]);
Console.WriteLine("Index: {0} Value: {1}",
index_4, greetings[index_4]);
}
}
}
输出：
Index: 0 Value: Hello
Index: 1 Value: Hola
Index: 4 Value: Ohayo
Index: 5 Value: Ahnyounghaseyo