字符加扰（C＃和Javascript）

Question

I need to scramble chars in word. And this scrambling must not be random. In other words, each time of scrambling (on the same word) the new result must be equal to last scramble result (on the same word). Very simple example is XOR. But XOR is very easy to decode and I need something more strength. Could you recommend library for such purpose that identically works on C# and Javascript?

Thank you for any advice!:)

Answer 1

You can use random with fixed seed if you really want to scramble characters:

string input = "hello";
char[] chars = input.ToArray();
Random r = new Random(2011); // Random has a fixed seed, so it will always return same numbers (within same input)
for (int i = 0 ; i < chars.Length ; i++)
{
    int randomIndex = r.Next(0, chars.Length);
    char temp = chars[randomIndex];
    chars[randomIndex] = chars[i];
    chars[i] = temp;
}
return new string(chars);

Answer 2

Although I don't really agree about what you were trying to do, here's a link to MD5 javascript library (assuming what you're trying to do is some kind of encryption). As for the C# part, it's a built in feature .

Answer 3

You can use any of the built in .NET classes to generate random numbers and use these to scramble your string. For all the subsequent scramble attempts you can use the result from the first scramble operation. This assumes that the result from the first call is stored somewhere.