internal static string CreateRandomString(Random rndGen, int size, string charsToUse)
{
int maxSize = CreatorSettings.MaxStringLength;
// invalid per the XML spec (http://www.w3.org/TR/REC-xml/#charsets), cannot be sent as XML
const string InvalidXmlChars = "\u0000\u0001\u0002\u0003\u0004\u0005\u0006\u0007\u0008\u000B\u000C\u000E\u000F\u0010\u0011\u0012\u0013\u0014\u0015\u0016\u0017\u0018\u0019\u001A\u001B\u001C\u001D\u001E\u001F\uFFFE\uFFFF";
const int LowSurrogateMin = 0xDC00;
const int LowSurrogateMax = 0xDFFF;
const int HighSurrogateMin = 0xD800;
const int HighSurrogateMax = 0xDBFF;
if (size < 0)
{
double rndNumber = rndGen.NextDouble();
if (rndNumber < 0.01)
{
return(null); // 1% chance of null value
}
size = (int)Math.Pow(maxSize, rndNumber); // this will create more small strings than large ones
size--;
}
StringBuilder sb = new StringBuilder();
for (int i = 0; i < size; i++)
{
char c;
if (charsToUse != null)
{
c = charsToUse[rndGen.Next(charsToUse.Length)];
sb.Append(c);
}
else
{
if (CreatorSettings.CreateOnlyAsciiChars || rndGen.Next(2) == 0)
{
c = (char)rndGen.Next(0x20, 0x7F); // low-ascii chars
sb.Append(c);
}
else
{
do
{
c = (char)rndGen.Next((int)char.MinValue, (int)char.MaxValue + 1);
} while ((LowSurrogateMin <= c && c <= LowSurrogateMax) || (InvalidXmlChars.IndexOf(c) >= 0));
sb.Append(c);
if (HighSurrogateMin <= c && c <= HighSurrogateMax) // need to add a low surrogate
{
c = (char)rndGen.Next(LowSurrogateMin, LowSurrogateMax + 1);
sb.Append(c);
}
}
}
}
return(sb.ToString());
}
private static string XmlValidChars(string token)
{
if (string.IsNullOrEmpty(token))
{
return(token);
}
try
{
return(XmlConvert.VerifyXmlChars(token));
}
catch (XmlException)
{
return(InvalidXmlChars.Replace(token, string.Empty));
}
}