gistfile1.cs

public string jiemi(string PlainStr, string key)
{
    string str3;
    int num2 = 1;
    if ((Strings.Len(PlainStr) % 2) == 0)
    {
        string str4 = Strings.StrReverse(Strings.Left(PlainStr, (int) Math.Round((double) (((double) Strings.Len(PlainStr)) / 2.0))));
        string str5 = Strings.StrReverse(Strings.Right(PlainStr, (int) Math.Round((double) (((double) Strings.Len(PlainStr)) / 2.0))));
        PlainStr = str4 + str5;
    }
    int num3 = Strings.Len(PlainStr);
    for (int i = 1; i <= num3; i++)
    {
        string str6 = Strings.Mid(PlainStr, i, 1);
        string str2 = Strings.Mid(key, num2, 1);
        if (((((Strings.Asc(str6) ^ Strings.Asc(str2)) < 0x20) | ((Strings.Asc(str6) ^ Strings.Asc(str2)) > 0x7e)) | (Strings.Asc(str6) < 0)) | (Strings.Asc(str6) > 0xff))
        {
            str3 = str3 + str6;
        }
        else
        {
            str3 = str3 + StringType.FromChar(Strings.Chr(Strings.Asc(str6) ^ Strings.Asc(str2)));
        }
        if (num2 == Strings.Len(key))
        {
            num2 = 0;
        }
        num2++;
    }
    return str3;
}