Invalid Base error when converting Java Base 27 Conversion function to C#

Question

I can't seem to get this to work after converting it to C#

I need it to work like the Java one but I can't seem to be able to do that what am I doing wrong?

Can anyone supply a fix and explain it please?

C#:

public static string Encrypt1(string strIn)
{

    string strOut = "";
    int lenIn = strIn.Length;
    int i = 0;

    while (i < lenIn)
    {
        double numRand = (int)Math.Floor(new Random().NextDouble() * 66) + 36;
        strOut += Convert.ToString((int)(strIn[i] + (char)numRand), 27) +
                Convert.ToString((int)numRand, 27);
        i++;
    }
    return strOut;
}

Java:

public String Encrypt1(String strIn) {

    String strOut = "";
    int lenIn = strIn.length();
    int i = 0;

    double numRand;

    while (i < lenIn) {
        numRand = Math.floor(Math.random() * 66) + 36;
        strOut += Integer.toString((int)(strIn.charAt(i) + (char)numRand), 27) +
                Integer.toString((int)numRand, 27);
        i++;
    }
    return strOut;
}

The error:

An unhandled exception of type 'System.ArgumentException' occurred in mscorlib.dll

Additional information: Invalid Base.

Error line:

   strOut += Convert.ToString((int)(strIn[i] + (char)numRand), 27) +
            Convert.ToString((int)numRand, 27);

`numRand = Math.floor(Math.random() * 66) + 36;` says 36 in java and 33 in C# — c_str, May 07 '16 at 06:02
What exactly are you trying to achieve and what errors do you get? — Jake, May 07 '16 at 06:05
Added the error am basically trying to encrypt a string am going to try to convert the decrypt function after this. — Punxor, May 07 '16 at 06:07
Unrelated, but you probably don't want to do `new Random()` *inside* the loop. — Andreas, May 07 '16 at 06:11
It appears you will need to [roll your own conversion](http://stackoverflow.com/q/923771/314291) to get a number in base 27. Convert.ToString only supports bases [2, 8, 10 or 16](https://msdn.microsoft.com/en-us/library/14kwkz77.aspx) — StuartLC, May 07 '16 at 06:17

Tim Ashton · Answer 1 · 2016-05-07T06:36:59.270

-2

This works with base 16.

public static string Encrypt1(string strIn)
{
    int radix = 16;

    string strOut = "";
    int lenIn = strIn.Length;
    int i = 0;

    double numRand;
    Random random = new Random();

    while (i < lenIn)
    {
        numRand = (int)Math.Floor(random.NextDouble() * 66) + 36;
        strOut += Convert.ToString((strIn[i] + (int)numRand), radix)  + 
            Convert.ToString((int)numRand, radix);
        i++;
    }
    return strOut;
}

edited May 07 '16 at 06:36

answered May 07 '16 at 06:04

Tim Ashton

436
6
18

Ahh, so this throws an exception.. Let me check it out. – Tim Ashton May 07 '16 at 06:10
@Puxnor, this works with base 16. See StuartLC's comment. – Tim Ashton May 07 '16 at 06:38

Invalid Base error when converting Java Base 27 Conversion function to C#

1 Answers1