Variables - pass by value or reference

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1

Hi, just a quick question to understand how the variable system works in UiPath… Are all variables passed by value or are there some cases where references are used?

E.g.
String a = “Test1”
String b = a
a = “Test2”
b = ?

2

hi @DEATHFISH,

Here the value of b will be test1 only as it works by passed by value logic. Attaching a sample workflow for your reference.

Regards,
Shiva KathikReference.xaml (4.7 KB)

3

Actually, there are some variables treated like Objects that are by default assigned by reference, not by value. For instance, the DataTable.
@Shiva_Karthik is right, the String is treated as a primitive in his example.

Like I’ve said, if you copy a DataTable, its reference is copied by default (shallow copy).
Consider the following assignments:

DataTable second = DataTable first
second.Rows(0)(0) = “modified value”

At this point, first(0)(0) will also be “modified value”.

Also, if you modify a DataRow which is part of a DataTable, the result will be modified in the DataTable also.

It would be nice to have a list of variable types and the way in which UiPath passes the content (value or reference). I think that the String object does not inherit by default UiPath’s generic “Object[]” (i.e. it is by default “unboxed”), while DataTable does.

Maybe someone can come with further details.

Regards,
Daniel

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