Microsoft VBScript runtime error '800a000d' Type mismatch: 'LastID' - vbscript

Question

I do a function to assign an ID. But when I click button, this error comes out.
Microsoft VBScript runtime error '800a000d' Type mismatch: 'LastID'
Public function AssignSanctionID(DeptID,SectID,SanctionType)
REM obtain Transaction ID
dim CmdX
dim SQLX
dim RsX
dim Prefix
dim LastID
dim CurrID
dim NewCurrID
'- Set Connection
HariNi=now()
Tahun=year(HariNi)
Bulan=month(HariNi)
if len(bulan)=1 then
Bulan= "0" & Bulan
end if
If Cint(Tahun) < 2016 then
Pref1= DeptID & "/" & SectID & "/"
Prefix=DeptID & "/" & SectID & "/" & Tahun & "/" & Bulan & "/"
else
Pref1= DeptID & "/%/" & SectID
Prefix=DeptID & "/" & Tahun & "/" & Bulan & "/"
end if
set CmdX = server.CreateObject("ADODB.Command")
Set RSX = Server.CreateObject("ADODB.Recordset")
SQLX = " SELECT * FROM Sanction " _
& " WHERE SanctionID like '%" & Pref1 & "%' " _
& " ORDER BY ID DESC"
CmdX.ActiveConnection = objconn
CmdX.CommandText = SQLX
RsX.Open CmdX,,0,1
if not(RsX.BOF and RsX.EOF) then
If Cint(Tahun) < 2016 then
LastID = right(RsX("ID"),4)
else
LastID = mid(RsX("ID"),13,4)
end if
else
if Bulan="04" then
LastID=0
end if
end if
RsX.Close
set RsX = nothing
'Set ID
If LastID<>"" then
'CurrID = left(4)
CurrID=int(LastID)+1
end if
if len(currid)>0 then
select case len(currid)
case 1
newcurrid = "000" & currid
case 2
newcurrid = "00" & currid
case 3
newcurrid = "0" & currid
case 4
newcurrid = currid
end select
else
NewCurrID="0001"
end if
If Cint(Tahun) < 2016 then
NewCurrID=Prefix & NewCurrID
else
NewCurrID=Prefix & NewCurrID & "/" & SectID
end if
AssignSanctionID = NewCurrID
end function

Answer 1

Hard to help if I don't see the data.
From quick view of the code the issue is here:
CurrID=int(LastID)+1
You are trying to cast LastID but are you sure that it is convertible? Could list all possible values?

Answer 2

Short answer: CInt only works with Numerical values. If you have letters in your value, then Cint wont work.
Bit longer answer:
Having read the Blog that we should be more welcoming (https://stackoverflow.blog/2018/04/26/stack-overflow-isnt-very-welcoming-its-time-for-that-to-change/?cb=1), here is a very general answer, but that might lead you on the correct way to fix it yourself.
Type Mismatch is an error you can get when using a variable the wrong way. For example if you try to do numerical functions with Strings (which means the variable contains letters a-z etc) you will get "Type Mismatch" as you cant add or subtract text in a mathematical way... On the other hand you cant add Integer variables (the variable only contains a number AND isnt contained within "quote marks").
So below is a few ways to assigna a variable and what type it becomes:
LastID=1 'This makes LastID an INT (number)
LastID="1" 'This makes LastID a String but a CInt(LastID) can turn it into an INT because it ONLY contains numbers.
LastID="IT" 'This makes LastID a String that CANT in any way be cast to INT as it contains letters.
LastID=IT 'This row will either create an error except if you already have a variable called IT, then LastID will get the same value as the IT variable...
This should hopefully get you on your way to fix this issue...