VBA：DateDiff 不返回确切的工作日

Question

my general manager asked me to track the working days of our company's current projects that is recorded in an excel file and he wanted to me to make a new column for the remaining working days. I tried to make below code a function from the net to get the range of the days:

Function RDays(pDate1 As Date, pDate2 As Date) As Long
    RDays = DateDiff("d", pDate1, pDate2)
End Function

but the results that i only get a value of 31 as a maximum days and when the value is greater than 31, the value returns to 1..

What would be the problem of this code?

Answer 1

The excel in-built NETWORKDAYS(start_date, end_date, [holidays]) function will work perfectly well for returning the number of working days between two dates.

More info: https://support.office.com/en-ie/article/networkdays-function-48e717bf-a7a3-495f-969e-5005e3eb18e7

Answer 2

Well, for one thing, it's Datedif in Excel, not Datediff, which is SQL Server.

Here is the general function, with arguments:

=DATEDIF (start_date, end_date, unit)

Here are the arguments, in units:

Unit    Return value
"Y"     Difference in complete years
"M"     Difference in complete months
"D"     Difference in days
"MD"    Difference in days, ignoring months and years
"YM"    Difference in months, ignoring days and years
"YD"    Difference in days, ignoring years