C# Substring

To get Substring of a string in C#, use Substring function on the string.

string.Substring(int startIndex, int length)

where

startIndex is the index position in the string from which substring starts.

length is the length of the substring.

length is optional. So, if you provide only startIndex, the substring starting from startIndex till the end of given string is returned by the Substring.

Example 1 – C# Sustring – Using startIndex

In the following example, we will find the substring with startIndex.

Program.cs

using System;

namespace CSharpExamples {

    class Program {
        static void Main(string[] args) {
            string str = "HelloWorld";
            int startIndex = 4;

            string substring = str.Substring(startIndex);
            Console.WriteLine("Substring is : "+substring);
        }
    }
}

Output

PS D:\workspace\csharp\HelloWorld> dotnet run
Substring is : oWorld
C# Substring - startIndex

Example 2 – C# Sustring – Using startIndex and length

In the following example, we will find the substring with startIndex.

Program.cs

using System;

namespace CSharpExamples {

    class Program {
        static void Main(string[] args) {
            string str = "HelloWorld";
            int startIndex = 4;
            int length = 3;

            string substring = str.Substring(startIndex, length);
            Console.WriteLine("Substring is : "+substring);
        }
    }
}

Output

PS D:\workspace\csharp\HelloWorld> dotnet run
Substring is : oWo
C# Substring

Example 3 – C# Sustring

In the following example, we will read the string, startIndex and length from the user and then find the substring.

Program.cs

using System;

namespace CSharpExamples {

    class Program {
        static void Main(string[] args) {
            Console.Write("Enter a string : ");
            string str = Console.ReadLine();

            Console.Write("Enter startIndex : ");
            int startIndex = Convert.ToInt32(Console.ReadLine());

            Console.Write("Enter length : ");
            int length = Convert.ToInt32(Console.ReadLine());

            string substring = str.Substring(startIndex, length);
            Console.WriteLine("Substring is : "+substring);
        }
    }
}

Output

PS D:\workspace\csharp\HelloWorld> dotnet run
Enter a string : Welcome to TutorialKart for C# Tutorial.
Enter startIndex : 5
Enter length : 12
Substring is : me to Tutori

PS D:\workspace\csharp\HelloWorld> dotnet run
Enter a string : TutorialKart
Enter startIndex : 5
Enter length : 3
Substring is : ial

Summary

In this C# Tutorial, we learned to find substring of a string with the help of examples.