在許多編程語言中，substring 方法或函數用于從一個給定的字符串中提取一部分字符

1. Python:

string = "Hello, World!"
start_index = 0
end_index = 5
sub_string = string[start_index:end_index]
print(sub_string)  # 輸出 "Hello"

2. JavaScript:

let string = "Hello, World!";
let startIndex = 0;
let endIndex = 5;
let subString = string.substring(startIndex, endIndex);
console.log(subString);  // 輸出 "Hello"

3. Java:

public class Main {
    public static void main(String[] args) {
        String string = "Hello, World!";
        int startIndex = 0;
        int endIndex = 5;
        String subString = string.substring(startIndex, endIndex);
        System.out.println(subString);  // 輸出 "Hello"
    }
}

4. C#:

using System;

class Program {
    static void Main() {
        string str = "Hello, World!";
        int startIndex = 0;
        int length = 5;
        string subStr = str.Substring(startIndex, length);
        Console.WriteLine(subStr);  // 輸出 "Hello"
    }
}

注意：不同編程語言中 substring 方法的參數和行為可能略有不同。請根據所使用的編程語言查閱相應文檔。