public static NumMatch Match(string input, int start)
{
var nm = new NumMatch();
var typeCache = NumType.unknown;
if (string.IsNullOrEmpty(input) || start < 0)
{
return(nm);
}
DFAState cur = _start;
DFAState pre = null;
for (int i = start; i < input.Length; i++)
{
pre = cur;
cur = cur.Process(input[i]);
if (cur == null)
{
if (!pre.IsTerminal) // 上一个状态非终止状态
{
nm.Length--;
}
return(nm);
}
if (cur.Type == NumType.signed)
{
nm.IsSigned = true;
}
nm.Length++;
if (cur.IsTerminal)
{
if (typeCache > nm.Type)
{
nm.Type = typeCache;
}
}
if (cur.Type > nm.Type)
{
if (cur.IsTerminal)
{
nm.Type = cur.Type;
}
else
{
typeCache = cur.Type;
}
}
}
return(nm);
}