Option: JoinCol Datacolumn Expression
hava a sample data like
and an array with the current JoinColumns, which can dynamic created
then we can dynamicly generate the helper column Expression string:
and set it as Expression to the helper column
As you see in the flow:
with the help of expression the helper col is filled / populated wthout any loop in one go
before:
after setting the expression
with the conversion to string we also handle different datatypes
Option LINQ / ForEach
just fill up the helper col before joining. populating the helper col can also be dynamized