public LSL_String llGetSubString(string src, int start, int end)
{
if (!ScriptProtection.CheckThreatLevel(ThreatLevel.None, "LSL", m_host, "LSL", m_itemID)) return new LSL_String();
// Normalize indices (if negative).
// After normlaization they may still be
// negative, but that is now relative to
// the start, rather than the end, of the
// sequence.
if (start < 0)
{
start = src.Length + start;
}
if (end < 0)
{
end = src.Length + end;
}
// Conventional substring
if (start <= end)
{
// Implies both bounds are out-of-range.
if (end < 0 || start >= src.Length)
{
return String.Empty;
}
// If end is positive, then it directly
// corresponds to the lengt of the substring
// needed (plus one of course). BUT, it
// must be within bounds.
if (end >= src.Length)
{
end = src.Length - 1;
}
if (start < 0)
{
return src.Substring(0, end + 1);
}
// Both indices are positive
return src.Substring(start, (end + 1) - start);
}
// Inverted substring (end < start)
// Implies both indices are below the
// lower bound. In the inverted case, that
// means the entire string will be returned
// unchanged.
if (start < 0)
{
return src;
}
// If both indices are greater than the upper
// bound the result may seem initially counter
// intuitive.
if (end >= src.Length)
{
return src;
}
if (end < 0)
{
return start < src.Length ? src.Substring(start) : String.Empty;
}
if (start < src.Length)
{
return src.Substring(0, end + 1) + src.Substring(start);
}
return src.Substring(0, end + 1);
}
