Variables - check if exists

nleitgeb — Tue, 23 Aug 2016 09:18:31 GMT

Hi there,

I´ve got some scripts in one QVW and it`s necessary to reload the script parts at different times. The reason is very easy, the raw datas exits at different times, so I can`t reload everything at once.

At the moment I`ve solved this with variables, that`s a very easy solution. These variables were declared once and setting by button constantly. With an if clause in the script it`s possible to activate /deactivate some parts (eg. if $(vScriptVariable1) = 1 then [reload script part1…]… else [do nothing…] end if [and start with the next if $(vScriptVariable2) = 1). Actually there are about 20 script parts controlled with this solution.

But I`m not absolutely happy with this solution, because it`s possible to delete these variables and I have to declare again (regularly I delete all the variables especially to check correct initialization etc.). On the other hand I don`t like to declare these variable at every reload, because I`d like to know which script parts already done (shown by $( vScriptVariable1) ) = 1).

So, is there a way to check if a variable exists? (To be clear: I don’t need the value of the variable rather if the variable is declared!)

I´ve tried this with isnull($(vScriptVariable1)) nd with exists(($(vScriptVariable1)) but it doesn’t work.

The variable vTest in the example is just declared in order to show which case (Then or Else) is valid. Of course I´ve tried with a deleted vScriptVariable1 and a declared vScriptVariable1.

Any ideas?

Many thanks,

Nicole

Re: Variables - check if exists

tamilarasu — Tue, 23 Aug 2016 10:35:04 GMT

Hi Nicole,

Try this,

If Len(Trim('$(vScriptVariable1)')) = 0 then

Set vTest = 'Then';

Else

Set vTest = 'Else';

End If

Re: Variables - check if exists

sunny_talwar — Tue, 23 Aug 2016 10:39:53 GMT

Can you try this:

If IsNull('$(vScriptVariable1)') then

If Len(Trim('$(vScriptVariable1)')) = 0 then

Re: Variables - check if exists

nleitgeb — Tue, 23 Aug 2016 12:26:12 GMT

Hi Tamil, hi Sunny,

many thanks!! This works perfect!

Of course I also tried the isnull('$()') solution but unfortunately it doesn`t work; function len(trim('$()') works perfect, Thank you for this perfect solution, it helps soo much,

BG,

Nicole

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