Create Zip Rar And Gzip Files Using .Net

public static string GenerateRandomString(int length)

{

//It will generate string with combination of small,capital letters and numbers

    char[] charArr ="0123456789ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz".ToCharArray();

    string randomString = string.Empty;

    Random objRandom = new Random();

    for (int i = 0; i < length; i++)

    {

        //Don't Allow Repetation of Characters

        int x = objRandom.Next(1, charArr.Length);

        if (!randomString.Contains(charArr.GetValue(x).ToString()))

            randomString += charArr.GetValue(x);

        else

            i--;

    }

    return randomString;

}

To generate the random string with only capital letters then change charArr[] to below.

// to generate random string only with capital letters

char[] charArr = "ABCDEFGHIJKLMNOPQRSTUVWXYZ".ToCharArray();

To generate the random string with only small  letters then change charArr[] to below.

// to generate random string only with small letters

char[] charArr = "abcdefghijklmnopqrstuvwxyz".ToCharArray();