String Reverse related questions in C# which is frequently ask in the interview

Q How to reverse a string in C# using predefined method ToCharArray()

using System;

using System.Collections.Generic;

using System.Linq;

using System.Text;

using System.Threading.Tasks;

namespace ReverseStringConcept

{

class Program

{

static void Main(string[] args)

{

string strInput = null, strOutput = null;

Console.WriteLine("enter a string to revers");

strInput = Console.ReadLine();

char[] charInput = strInput.ToCharArray();

for (int i = charInput.Length-1; i >=0; i--)

{

strOutput = strOutput + strInput[i];

}

Console.WriteLine("reverse---->" + strOutput);

Console.ReadLine();

}

}

}

//ToCharaArray[]è

Copies the characters in this instance to a Unicode character array.

        //

        // Returns:

        //     A Unicode character array whose elements are the individual characters of

        //     this instance. If this instance is an empty string, the returned array is

        //     empty and has a zero length.

Q. How to reverse a string without any pre define function ?

using System;

using System.Collections.Generic;

using System.Linq;

using System.Text;

using System.Threading.Tasks;

namespace ReverseStringConcept

{

class Program

{

static void Main(string[] args)

{

string strInput = null, strOutput = null;

int Length;

Console.WriteLine("enter a string to revers");

strInput = Console.ReadLine();

Length = strInput.Length - 1;

while (Length >= 0)

{

strOutput = strOutput + strInput[Length];

Length--;

}

Console.WriteLine("reverse   -->" + strOutput);

Console.ReadLine();

}

}

Output

Q Find given String is a palindrom or not?

using System;

using System.Collections.Generic;

using System.Linq;

using System.Text;

using System.Threading.Tasks;

            

namespace ReverseStringConcept

{

class Program

{

static void Main(string[] args)

{

string strInput = null, strOutput = null;

Console.WriteLine("enter a string to ");

strInput = Console.ReadLine();

char[] charInput = strInput.ToCharArray();

for (int i = charInput.Length- 1; i >= 0; i--)

{

strOutput = strOutput + charInput[i];

}

//Console.WriteLine(strInput);

//Console.WriteLine(strOutput);

if (strOutput == strInput)

{

Console.WriteLine("palindrom");

}

else

{

Console.WriteLine("Not a palindrom");

}

Console.ReadLine();

}

}

}

Output:

Q. Reverse  the string words  in the same position

using System;

using System.Collections.Generic;

using System.Linq;

using System.Text;

using System.Threading.Tasks;

namespace ReverseStringConcept

{

class Program

{

static void Main(string[] args)

{

string strInput = null, strOutput = null;

Console.WriteLine("enter a string to ");

strInput = Console.ReadLine();

string[] words = strInput.Split(' ');

for (int i = 0; i <= words.Length-1; i++)

{

char[] charInput = words[i].ToCharArray();

for (int j = charInput.Length-1; j >=0; j--)

{

strOutput = strOutput + charInput[j];

}

strOutput += " ";

}

Console.WriteLine("reverse---->" + strOutput);

Console.ReadLine();

}

}

}

Output: