Unanswered

Question about Context Variables and Clearing an Object Data Type

(0) Share

Report

Posted on by tly

400

This is one of those weird questions where it may have already been discussed, but hidden behind unexpected subject terms. If this is the case, can you please supply a link? Thanks.

So I've been playing around with the idea of assigning objects to context variables (as well as collection fields). For example:

UpdateContext(myContextVariable, First(Filter(myCustomerSPList, ID=100)))

Once I've assigned myContextVariable to this item, I can refer to my customer as myContextVariable.FirstName. This is my intention. Now, I run some subsequent filters based on this data, so at some point, I'd like to clear out this data.

If I type in Clear(myContextVariable), I get an error because it's not a "collection" data type. If I type UpdateContext(myContextVariable, ""), I also get an error because it's not a "text" data type. It's an "object" data type. How do you clear that? Thanks.

https://docs.microsoft.com/en-us/powerapps/maker/canvas-apps/functions/function-updatecontext

Categories:

Building Power Apps

I have the same question (0)

All responses (5)

Answers (1)

Community Power Pla... on at

Like (1)

Report
Hi tommyly

Interesting that your function below worked as well.
UpdateContext(myContextVariable, First(Filter(myCustomerSPList, ID=100)))
I usually work with the following syntax as indicated in the documentation site you referred to:
UpdateContext( { ContextVariable: Value})

This would suggest that updating your context variable may be possible using:
UpdateContext ( { myContextVariable: "" } )

Was this reply helpful? Yes No
Verified answer

Scobie 122 on at

Like (9)

Report

Hi @tommyly,

This was interesting as I hadn't thought much about a context variable being a object or record type.

To Clear this value for the vaiable you can make use of the Blank() function . As shown here:
https://docs.microsoft.com/en-us/powerapps/maker/canvas-apps/functions/function-isblank-isempty

using the syntax:
UpdateContext({myContextVariable: Blank()})

Scobie

Was this reply helpful? Yes No
tly 400 on at

Like (0)

Report

That seems to do the job. Thanks!

Was this reply helpful? Yes No
salvadorplj 9 on at

Like (1)

Report
The safest way to clear a variable is by being explit about the data type you hold in it, that way you wont have any issues if processes' steps intermix.

Instead of:
UpdateContext({SunShine: Blank()});
Do:
UpdateContext({SunShine: DateTimeValue(Blank())});

Was this reply helpful? Yes No
Golly 127 on at

Like (0)

Report

Be careful with setting variables to Blank()! If you are storing a formula or strings with string interpolation in the variable, Blank() will store in the variable instead of clearing it, resulting in the variable clearing the value where you're using it.

Was this reply helpful? Yes No