Do program.prg

[FoxWing]

Hi,

I'm trying to execute a DO statement as follows :
DO check_status WITH 'T'

However, my check_stauts.prg has a RETURN statement.

How can i able to 'read' the return result from my prg program ?


Many thanks

 

[darrellblackhawk]

One of 4 ways:

1- Define a private variable which the called program
knows about.

2- Pass in the name of the private variable in
a character variable (better)


3- Redesign so you can call it as a function and pass a variable by reference

4- Same as 3, but just return the value

* 3-4 can also be easily accomplished by issuing a
* set procedure to (program name) additive and calling
* your program as a function


1-
private vReturn
vReturn = .f. && Have to define the var
DO check_status WITH 'T'

procedure check_status
lparam vArg1
* Processing...

vReturn = somevalue

2-
private vReturn
vReturn = .f. && Have to define the var
DO check_status WITH 'T', "vReturn"

procedure check_status
lparam vArg1, vReturnVal
* Processing...

&vReturnVal = somevalue

3-
local vReturn
=check_status('T',@vReturn)

procedure check_status
lparam vArg1, vReturnValue
* Processing...

vReturnValue = somevalue

4-
local vReturn
vReturn = check_status WITH 'T'

procedure check_status
lparam vArg1
* Processing...

return somevalue

 

[darrellblackhawk]

Forgot about globals(public) variables which can be the worst choice of all, but sometimes the most expedient.

Darrell

 

[FoxWing]

thank you very much for the quick response.

 

[alvechurchdata]

All the above will work but Check_Status is being used as a function so the most straightforward way would be to call it as a function:

Result = CheckStatus(.T.)



Geoff Franklin

http://www.alvechurchdata.co.uk

 

[Mike Lewis]

FoxWing,

I agree with Geoff. If Check_Status is returning a value, it should be a function, not a procedure.

Mike


__________________________________
Mike Lewis (Edinburgh, Scotland)

My sites:
Visual FoxPro (www.ml-consult.demon.co.uk)
Crystal Reports (www.ml-crystal.com)

 

[wgcs]

Just a couple notes:

VFP doesn't care whether a routine is declared as a FUNCTION or a PROCEDURE ... they are identical. The difference is simply as documentation. Both always return a value (which is .T. unless otherwise specified).

And, Number 4 above:
local vReturn
vReturn = check_status WITH 'T'

procedure check_status
lparam vArg1
* Processing...

return somevalue

...Has a syntax error: you cannot use "WITH" if you are calling a subroutine and assigning its result to a variable... this would work instead:

local vReturn
vReturn = check_status('T')

procedure check_status
lparam vArg1
* Processing...
return somevalue

- Bill

Get the best answers to your questions -- See FAQ481-4875.

 

[darrellblackhawk]

You're correct wgcs, that was my mistake in haste.

Darrell