Robert wrote:
>
> Hi, all.
>
> I need you to help me, please
> I'm programming in MapBasic and I have trouble doing some procedures.
> For example I have the nex table
>
> Table One.tab with the next fields
> Table One.tab
> A1 B1 C1 D1
> A1 B2 C2 D2
> A3 B3 C3 D3
>
> Browse this table without problems, but I need to know, How to do in =
> order to know if this table is OPEN or not?, afterthat to close it.
If you know the name of a table, you can check to see if it's open
with a function like the following:
Function IsTableOpened (
ByVal sTab As String) 'Name of (possibly) open table
as logical 'TRUE is table is open
dim i as smallint
OnError goto Trap
i = TableInfo (sTab, TAB_INFO_NUM)
IsTableOpened = TRUE
exit function
Trap:
IsTableOpened = FALSE
End Function
This simply sets up a trap routine to catch errors, and then tries
to execute TableInfo(). We don't even care what the result is; just
did it work or not? If it works, the table is open and
IsTableOpened() returns TRUE. If the table is not open, then
TableInfo() generates a runtime error, and the error trap routine
returns FALSE.
You can get more elaborate (like suppose the table is open but not
with the name you think it has, or perhaps you need to check only
for tables with four columns named A1, B1, C1, D1), but this is a
quick and general method to see if a table is open providing you the
table name.
--
- Bill Thoen
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