SSRS Reporting Expression to Split Full Name Field - reporting-services

Question

I've been trying to get this to behave with no luck.
The database base field only has FULL NAME field, which includes Middle initials on some cases and no middle initials in some other cases.
I've been trying to display LastName, FirstName by using this ssrs expression below: While this works in names that doesn't have middle initials or name on the field.... for those names that includes middle initials/name, we run into issues with displaying.
=Right(Fields!agent_name.Value,Len(Fields!agent_name.Value)-Instr(Fields!agent_name.Value," ")) & ", " & (Left(Fields!agent_name.Value,Instr(Fields!agent_name.Value," ")))
But it includes the Middle Initials to display first.. As an example:
If the fullname field is John S Doe, above expression displays as:
S Doe, John
What I need to display is:
Doe, John
How do I set my expression to get rid of the Middle initial/name to display?
I've done a great amount of research and tried many diff expressions but no luck.. thanks in advance.

Answer 1

While slightly inefficient, this is a clean way to accomplish the result:
=Split(Fields!agent_name.Value," ")(Split(Fields!agent_name.Value," ").Length-1) + ", " + Split(Fields!agent_name.Value," ")(0)
Edit: The above indeed does not work with suffixes. The expression below will remove a middle initial if its the second name and has a length of 1, which you could use in a calculated field. But it would fail for first name "Ann Marie" and the first/last swap would need to be handled separately.
=IIF(Split(Fields!agent_name.Value," ")(1).Length=1,Replace(Fields!agent_name.Value, " " + Split(Fields!agent_name.Value," ")(1) + " "," "),Fields!agent_name.Value)
The short of it is that you really would be best served handling this in code. But even so, if your fullname field is space-inclusive beyond what you want to seperate on there arises the potential for ambiguous cases, like the suffix- and initial-less "Ann Marie van Der Beek".

Answer 2

Try using this expression:
=RIGHT(
Fields!agent_name.Value,LEN(Fields!agent_name.Value)-InStrRev(Fields!agent_name.Value," "))
& ", " & LEFT(
Fields!agent_name.Value,
InStr(Fields!agent_name.Value," ")-1
)
It is a native SSRS solution however I recommend using custom code to get an maintainable solution.
UPDATE: Regex solution:
=System.Text.RegularExpressions.Regex.Replace(
Fields!agent_name.Value,
"(\w+)\s+(\w+\.*\s)?(\w+)",
"$3, $1"
)
Let me know if this helps.