Generate Random String in C# and Vb.net

In this method just pass the length , it will generate a random string.

VB.net :

    Public Function GetRandomString(ByVal length As Integer) As String
        'use the following string to control your set of alphanumeric characters to choose from
        'you could also include lowercase or punctuation too
        Const alphabet As String = "ABCDEFGHIJKLMNOPQRSTUVWXYZ0123456789"


        Dim result As New StringBuilder(length)


        ' Random is not truly random,
        ' so we try to encourage better randomness by using a seed value
        Static rnd As New Random(Convert.ToInt32(DateTime.Now.Ticks And Integer.MaxValue))

        Dim prevChar As String = String.Empty
        Dim nextChar As String
        Do While result.Length < length
            nextChar = alphabet.Substring(rnd.[Next](0, alphabet.Length), 1)
            If nextChar.Equals(prevChar) = False Then
                result.Append(nextChar)
                prevChar = nextChar
            End If
        Loop
        Return result.ToString
    End Function


C#

   private static Random random = new Random();
        public static string GetRandomString(int length)
        {
            const string chars = "ABCDEFGHIJKLMNOPQRSTUVWXYZ0123456789";
            return new string(Enumerable.Repeat(chars, length)
              .Select(s => s[random.Next(s.Length)]).ToArray());
        }