private static string RandomString(int size, bool lowerCase = false)
{
var builder = new StringBuilder();
var random = new Random();
for (int i = 0; i < size; i++)
{
char ch = Convert.ToChar(Convert.ToInt32(Math.Floor(26 * random.NextDouble() + 65)));
builder.Append(ch);
}
if (lowerCase)
return builder.ToString().ToLower();
return builder.ToString();
}