/// <summary>
/// Token_Date follows the same rules for its parameters as Token_Int. It
/// expects day to precede months, and months to precede years, but it can
/// cope with D-M-Y and D-M-0 kinds of date. Token_Date is implemented as a
/// state-based parser:
///
/// State Next token Token means Go to state
/// ----- ---------- ----------- -----------
/// -1 Error
/// 0 Start of parsing Number Day of month 1
/// else -1
/// 1 Past day '/' or '-' Delimiter 2
/// JAN-DEC Month 3
/// else 2
/// 2 Numeric month 1-12 Month 3
/// else -1
/// 3 Past month '/' or '-' Delimiter 3
/// Number Year 4
/// else Year=0 4
/// </summary>
/// <param name="InSt"></param>
/// <param name="D"></param>
/// <returns></returns>
public static bool TokenDate(ref string InSt, ref int D)
{
bool result;
// We need to have these in upper case as that is how TextToken returns them
string[] MonthTexts = { "JAN", "FEB", "MAR", "APR", "MAY", "JUN", "JUL", "AUG", "SEP", "OCT", "NOV", "DEC" };
int State = 0;
int Day = 0;
int Mn = 0;
int Yr = 0;
while ((State != -1) && (State != 4))
{
switch (State)
{
case 0:
if (TokenInt(ref InSt, ref Day) && (Day >= 1) && (Day <= 31)) // State 0: we expect a number for the day
{
State = 1;
}
else
{
State = -1;
}
break;
case 1: if ((MatchToken(ref InSt, "/") || MatchToken(ref InSt, "-"))) // State 1: Day found, looking for a
{
State = 2; // delimiter or a month text
}
else
{
Mn = 1;
while ((Mn <= 12) && (!MatchToken(ref InSt, MonthTexts[Mn])))
{
Mn++;
}
if (Mn <= 12)
{
State = 3;
}
else
{
State = 2;
}
}
break;
case 2: if (TokenInt(ref InSt, ref Mn) && (Mn >= 1) && (Mn <= 12)) // State 2: Day/month delimiter found, so
{
State = 3; // looking for a numeric month
}
else
{
State = -1;
}
break;
case 3: if ((MatchToken(ref InSt, "/") || MatchToken(ref InSt, "-"))) // State 3: month has been found. Clear
{
State = 3; // away any delimiter and then look for a
}
else if (TokenInt(ref InSt, ref Yr) && (Yr >= 1)) // year
{
if (Yr < 100)
{
Yr = 1900 + Yr;
}
State = 4; // State=4 is the exit point
}
else
{
Yr = 0;
State = 4;
}
break;
}
}
if ((State != -1) && StdDate.DateValid(StdDate.DateVal(Day, Mn, Yr)))
{
result = true;
D = StdDate.DateVal(Day, Mn, Yr);
}
else
{
result = false;
}
return(result);
}
/// <summary>
/// Token_Date follows the same rules for its parameters as Token_Int. It
/// expects day to precede months, and months to precede years, but it can
/// cope with D-M-Y and D-M-0 kinds of date. Token_Date is implemented as a
/// state-based parser:
/// -----
/// State Next token Token means Go to state
/// ----- ---------- ----------- -----------
/// -1 Error
/// 0 Start of parsing Number Day of month 1
/// else -1
/// 1 Past day '/' or '-' Delimiter 2
/// JAN-DEC Month 3
/// else 2
/// 2 Numeric month 1-12 Month 3
/// else -1
/// 3 Past month '/' or '-' Delimiter 3
/// Number Year 4
/// else Year=0 4
/// </summary>
/// <param name="inputStr">Input date string</param>
/// <param name="dateValue">Returned date</param>
/// <returns>True is parsed ok</returns>
public static bool TokenDate(ref string inputStr, ref int dateValue)
{
bool result;
// We need to have these in upper case as that is how TextToken returns them
string[] monthTexts = { "JAN", "FEB", "MAR", "APR", "MAY", "JUN", "JUL", "AUG", "SEP", "OCT", "NOV", "DEC" };
int state = 0;
int day = 0;
int mn = 0;
int yr = 0;
while ((state != -1) && (state != 4))
{
switch (state)
{
case 0:
if (TokenInt(ref inputStr, ref day) && (day >= 1) && (day <= 31)) // state 0: we expect a number for the day
{
state = 1;
}
else
{
state = -1;
}
break;
case 1: if (MatchToken(ref inputStr, "/") || MatchToken(ref inputStr, "-")) // State 1: Day found, looking for a
{
state = 2; // delimiter or a month text
}
else
{
mn = 1;
while ((mn <= 12) && (!MatchToken(ref inputStr, monthTexts[mn])))
{
mn++;
}
if (mn <= 12)
{
state = 3;
}
else
{
state = 2;
}
}
break;
case 2: if (TokenInt(ref inputStr, ref mn) && (mn >= 1) && (mn <= 12)) // State 2: Day/month delimiter found, so
{
state = 3; // looking for a numeric month
}
else
{
state = -1;
}
break;
case 3: if (MatchToken(ref inputStr, "/") || MatchToken(ref inputStr, "-")) // State 3: month has been found. Clear
{
state = 3; // away any delimiter and then look for a
}
else if (TokenInt(ref inputStr, ref yr) && (yr >= 1)) // year
{
if (yr < 100)
{
yr = 1900 + yr;
}
state = 4; // state=4 is the exit point
}
else
{
yr = 0;
state = 4;
}
break;
}
}
if ((state != -1) && StdDate.DateValid(StdDate.DateVal(day, mn, yr)))
{
result = true;
dateValue = StdDate.DateVal(day, mn, yr);
}
else
{
result = false;
}
return(result);
}
