Pointer Variables

[Rhett Scott]

I would like to use a variable to load the name of a field in a record that I would like to update. But I'm thinking I may need to use the Pointer variable type and I don't understand the documentation in the book.

Here is the plain english code that I would like to use:

tbl.open table
find record to update
based on the values of the record (a series of in and out time clock punches) load a variable called "punch" with the name of the field that is to hold the next "punch"
tbl.change begin
tbl.punch=time()
change end
tbl.close

Can I load my field name into the variable call punch? and if so do I need to declare the variable in a special way? and once doing this what does the assignment statement look like?

Thanks for the help!!!

[Tom Cone Jr]

RE: Pointer Variables

Rhett,

I'll give this some thought.

In the meantime, I'm curious about something. why not put the in and out times in a linked one to many child table, instead of having multiple instances in each record? Unless I miss my guess your design is better suited for a spreadsheet than a relational dbf.

employee
  ||
   ==>TimeRecords

Where employee table contains one unique record per employee, and includes an idnumber of some sort, and
TimeRecords includes lots and lots of records, each of which includes an idnumber linking the current record back to the Employee table.

TimeRecords table could have this kind of structure:

idnum,   c,   5
dateworked,    d,    8
clockin,   c,   6
clockout,   c,   6

and so on.

More later,

-- tom

[Tom Cone Jr]

RE: Pointer Variables

Rhett,

here's an example to play with that might help.

Unzip to a separate folder. Do not mix with your development work.

-- tom

[Tom Cone Jr]

RE: Pointer Variables

Rhett,

the example in the previous post illustrates how to change the value stored in a field in a table, when the user specifies the name of the field, and supplies the new value.

It does this in Xbasic by getting a pointer to the desired field, and then using the fld.value_put() method. Something similar could be easily adapted for your case I believe.

-- tom

[russ Boehle]

RE: Pointer Variables

Here's how I did a time clock app. This is only part of it and it's not done. The part that they punch in on is in one database and the reports etc are in a different database for security reasons. Unzip this to a new directory. This should work but I did a backup and didn't test the backup. The approach here is pretty much what Tom is talking about. (And I'm sure he could do it better)

Russ