public static string GenerateStrings(int length)
 {
     var rsg = new RandomStringGenerator();
     rsg.IsUsingNumeric = true;
     rsg.IsUsingSpecialChars = true;
     rsg.IsUsingLowCase = true;
     rsg.IsUsingUpperCase = true;
     return rsg.Generate(length);
 }
 /// <summary>
 /// Generate a random string consisted of letters
 /// </summary>
 /// <param name="length">length of the string generated</param>
 /// <returns></returns>
 public static string GenerateLetterStrings(int length)
 {
     var rsg = new RandomStringGenerator();
     rsg.IsUsingNumeric = false;
     rsg.IsUsingSpecialChars = false;
     return rsg.Generate(length);
 }