UiPath Studio: Where is the documentation about the functions inside the valid VB expressions?

Can’t find developer documentation about UiPath functions syntax and arguments

Note: File Exists is just an example, usually this happend to me when trying to manipulate other kind of objects (arrays, Datatables) and try to make complex things.

Now lets go with the Situation:

I’m trying to verify if an element exists, so I can:

  1. Use the activity (https://docs.uipath.com/activities/docs/file-exists-x) or path exist
  2. Write VB command and invoke the code (FileSystem.FileExists(String) Method (Microsoft.VisualBasic.FileIO) | Microsoft Docs)

The problem comes when I try to use an assign activity with the VB or C# expression to make it faster, the sintaxis change, so, to make it work I have to change

VB → UiPaht (?)
FileExists (path as String); → file.Exists(path as String) or even use

But here is the thing… I’ve reached file.Exist after searching for the “file” dropdown expression’s menu, and I can’t see more documentation about it, just the informative box that appears when i hover the expression.

Even I don´t have a terminal where I can type something like help file to search for the documentation.

Note 2: The Value field of the assign activity says: Enter a VB expression, but it doesn’t work with the VB expression, it uses other syntax and methods for the expressions.

If someone knows where to find this kind of documentation and can share the link with me I would appreciate it a lot.


Welcome to uipath forum

Let’s go one by one

I believe there is no document for syntax or expressions that can be used in UiPath
There are documents that describes on how each activity can be used and those activities are almost the same what a block of c# or vb net code does
That’s more like custom activity building

Each activity in UiPath is made with block of codes on dot net basis only and the input argument been passed should be a single line of C# or vb net expression and not a block of code.

But I really like this idea of having a set of predefined expressions which can really help developers who have started their journey with coding
Hope this could be added as a feature in future releases

May be you can try with other set of activities instead of assign like
Invoke code activity
Invoke VBA activity

Cheers @veruttigianpier

1 Like

Hope this clarifies

Do you have any further queries to discuss on this topic


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