Return multiple data through a function

[n4rk0o]

Hello,

I try to return multiple values from a function but I didn't find any example.

In multiple forums, I read about ByRef, arrays, etc.

What I want to do is to return values by a function or something else but I didn't find how.

$strComputer = "127.0.0.1"

$objWMIService = ObjGet("winmgmts:" _
& "{impersonationLevel=impersonate}!\\" _
& $strComputer & "\root\sms")

$colComputers = $objWMIService.ExecQuery _
("Select * from SMS_Client")

Local $Components = ''"

For $objComputer in $colComputers
$Components = $objComputer.DisplayName
MsgBox(0,"", @CRLF & "Installed Components : " & $Components & @CRLF )
Next

I am a beginner so I don't have the keys to do that.

Maybe someone can help me.

Thanks a lot

[James]

You could store the return values in an array, the callee then loops through the returned array with the values you need.

[n4rk0o]

The same code in a function:

GetSMSInfos ("127.0.0.1")
Func GetSMSInfos ($strComputer)
$objWMIService = ObjGet("winmgmts:" _
& "{impersonationLevel=impersonate}!" _
& $strComputer & "rootsms")

;~ $colComputers = $objWMIService.ExecQuery _
;~ ("Select * from Win32_NTLogEvent")
$colComputers = $objWMIService.ExecQuery _
("Select * from SMS_Client")
Local $Components = ''
For $objComputer in $colComputers
$Components = $objComputer.DisplayName
Return $Components
Next
EndFunc

I tried a lot of things but in that state, the script return the first value and not all of it.

I would like to store all values in a variable (array or else) and return it but I didn't find how.

[Zedna]

#include <Array.au3>

$result = GetSMSInfos ("127.0.0.1")
$result = StringSplit($result, '|')
_ArrayDisplay($result)

Func GetSMSInfos ($strComputer)
    $objWMIService = ObjGet("winmgmts:" & "{impersonationLevel=impersonate}!" & $strComputer & "rootsms")

    ;~ $colComputers = $objWMIService.ExecQuery ("Select * from Win32_NTLogEvent")
    $colComputers = $objWMIService.ExecQuery ("Select * from SMS_Client")
    Local $Components = ''
    For $objComputer in $colComputers
        $Components &= $objComputer.DisplayName & '|'
    Next

    If $Components <> '' Then $Components = StringTrimRight($Components,1)
    Return $Components
EndFunc

Edited May 9, 2012 by Zedna

[jchd]

AutoIt functions are not multi-valued, that is: return at most one value.

So your problem turns into: how can we group several distinct values into one?

As the posted answers show, the simplest and cleanest way to achieve that is to store the multiple values into one array.

There are other ways you could use to perform a similar (but not identical) action:

pass ByRef parameter(s) that the callee function may change, effectively changing them in the caller function scope.

use global variables (dirty, messy, deprecated, don't do that)

return a structure built from DllCallStructCreate: reserved for specific, technical use.

Lookup the emphasized words in the help file to learn more.

[JohnOne]

I've used SetError also to return an extra 2 ints now and again.

[James]

I've used SetError also to return an extra 2 ints now and again.

There is a hole in your logic.

[JohnOne]

How so James?

If I return SetError(2664,2274,77592) am I not returning 3 values?

[jchd]

In this particular case, yes, technically, the caller may get them. But you can't pass back anything else than integers and doing so precludes using specific values for indicating error conditions in the callee function, restricting even more what you can "pass" back, not withstanding that you may have to introduce more error codes during the life of the function.

So all in all, this isn't a generic enough way of returning user values. And it's dirty, hugly, bad practice.

[James]

Following on from jchd, it's not idealogical to send back return statements in the errors. Erroneous values should be for error values only. It's illogical and definitely not good practise to be passing back a non-error value in the error handles.

[BrewManNH]

@extended is used in some functions that return as successful as a valid value.

[James]

@extended is used in some functions that return as successful as a valid value.

I'm sure you're not saying @extended is for errors, but others may think so:

Extended function return - used in certain functions such as StringReplace.

[BrewManNH]

Well, @extended IS set with SetError, so to most people's thinking, it could be thought of as an error indicator, even though you can set it with SetExtended also (which I don't see all that often though there are examples to be found).

[James]

Well, @extended IS set with SetError, so to most people's thinking, it could be thought of as an error indicator, even though you can set it with SetExtended also (which I don't see all that often though there are examples to be found).

That's a good point.

I'm still a firm believer in not setting return values to an error indicator. Using SetExtended is probably a better way to go.

[BrewManNH]

I would agree with you on that point, definitely. I had the same issue myself with a example script I made until it was suggested that returning an array was better than setting the error/extended values and returning those.

[n4rk0o]

Thank you for the answers.

I will try it now

[JohnOne]

I am in agreement that it is bad practice, but I did say I have done it at times, and only to return ints.

The logic in that has no holes

If I needed to return a real error I might only set a negative number for example or some other value out of the

bounds of what is expected.

[n4rk0o]

Hello,

I just want to create a function like that but I would like to add a parameter to my function to change the argument in the loop For:

#include <Array.au3>
$result = GetSMSInfos ("127.0.0.1","Select * from SMS_Client", "ClientVersion")
$result = StringSplit($result, '|')
For $i = 1 to $result[0] Step 1
Msgbox(0,"",$result[$i])
Next
Func GetClientInfos ($strComputer, $Query, $ParamExt)
    $objWMIService = ObjGet("winmgmts:" & "{impersonationLevel=impersonate}!" & $strComputer & "rootccm")
    $colComputers = $objWMIService.ExecQuery ($Query)
    Local $Info = ''
    For $objComputer in $colComputers
        $Info &= $objComputer.ClientVersion & '|'
        $Info &= $objComputer.$ParamExt & '|'                               << Like That
    Next
    If $Info <> '' Then $Info = StringTrimRight($Info,1)
    Return $Info
EndFunc

Is it possible ?

Thank you

Edited May 10, 2012 by n4rk0o

[Zedna]

Try this

For $objComputer in $colComputers
        $Info &= $objComputer.ClientVersion & @TAB
;       $Info &= $objComputer.$ParamExt & '|'
        $Info &= Execute('$objComputer.' & $ParamExt) & '|'
    Next

[MilesAhead]

I am in agreement that it is bad practice, but I did say I have done it at times, and only to return ints.

The logic in that has no holes

If I needed to return a real error I might only set a negative number for example or some other value out of the

bounds of what is expected.

This makes me think of C coding. Since the design decision was made to take advantage of side effects in C anything other than 0 felt like something was assigned, and so should be considered a boolean True. But then they started using lots of error codes in functions. But by then the die was cast(no pun intended.) So then they got stuck with returning non-0 for success, but if you got an error, then call GetLastError() to get the error number. Then it all got flipped around with COM and HRESULT back to 0 being no error. It's kind of funny in a way. Life would have been simpler if they built in exceptions way at the beginning.

But what do I know? I like to slip in a "goto" now and then just to piss people off.

Edited May 11, 2012 by MilesAhead