Question

I have the following code. The function is to generate a random ID of a specific size. However i keep getting an error that says

‘System.Security.Cryptography.RNGCryptoServiceProvider’ does not contain a definition for ‘GetNonZeroBytes’ and no extension method ‘GetNonZeroBytes’ accepting a first argument of type ‘System.Security.Cryptography.RNGCryptoServiceProvider’ could be found (are you missing a using directive or an assembly reference)

I am trying to use the cryptography library in .NET and according to msdn this is one of the functions that can be used in this scenario but for some reason i keep getting this error.

Can anyone help?

using System;
using System.Net;
using System.Windows;
using System.Windows.Controls;
using System.Windows.Documents;
using System.Windows.Ink;
using System.Windows.Input;
using System.Windows.Media;
using System.Windows.Media.Animation;
using System.Windows.Shapes;
using System.Security.Cryptography;
using System.Text;

namespace ONeRESPONSEAPP
{
    public class IdGenerator
    {
        public static string GetUniqueKey(int maxSize)
        {
            char[] chars = new char[45];
            chars =
            "abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ1234567890".ToCharArray();
            byte[] data = new byte[1];
            RNGCryptoServiceProvider identity= new RNGCryptoServiceProvider();
            identity.GetNonZeroBytes(data);
            data = new byte[maxSize];
            identity.GetNonZeroBytes(data);
            StringBuilder result = new StringBuilder(maxSize);
            foreach (byte b in data)
            {
                result.Append(chars[b % (chars.Length)]);
            }
            return result.ToString();
        }
    }
}

Answer 1

System.Security.Cryptography.RNGCryptoServiceProvider.GetNonZeroBytes() is not supported by Windows Phone 7.
You might want to use RNGCryptoServiceProvider.GetBytes() instead, it is cryptographic strong as well.