Select Case with Function EndsWith()

Question

The code below works, I can't help thinking there is a better way to do this though. Is anyone experienced with using functions in conjunction with Select Statements.
The code I would expect to work would be something along the lines...

Select Case File.EndsWith()
Case "example 1", Case "example2"

This code works:

Select Case File.EndsWith(File)
    Case tFile.EndsWith("FileA.doc")
        sbExisting.AppendLine(Report.sbStart.ToString)
        sbExisting.AppendLine(Report.sbHeaders.ToString)
        sbExisting.AppendLine(Report.sbItems.ToString)
        sbExisting.AppendLine(Report.sbSubreport.ToString)
        sbExisting.AppendLine(Report.sbEnd.ToString)
        sbExisting.AppendLine(Report.sbCol.ToString)
    Case tFile.EndsWith("FileB.doc")
        'Slave
        sbExisting.AppendLine(Report.sbStart.ToString)
        sbExisting.AppendLine(Report.sbItems.ToString)
        sbExisting.AppendLine(Report.sbHeaders.ToString)
        sbExisting.AppendLine(Report.sbCol.ToString)
        sbExisting.AppendLine(Report.sbEnd.ToString)
End Select

I think just `Select Case True` would do it, instead of `Select Case tFile.EndsWith(tFile)` (which will always be true anyway) — Wug, Oct 19 '12 at 19:49
It actually works as expected with the code above; Properly distinguishing against either case. — Ccorock, Oct 19 '12 at 19:54
Just because something works as expected does not mean it's efficient or simple. — Wug, Oct 19 '12 at 19:57
I couldn't agree more. I was simply clarifying that the code itself works correctly. The intent of my post is to find an eloquent solution. — Ccorock, Oct 19 '12 at 20:00

GSerg · Accepted Answer · 2012-10-19T20:01:42.130

.EndsWith() returns true or false. That's all you have.

If you do want to use Select with that, then the idiomatic way is

Select Case True
    Case tFile.EndsWith("MSMaster.tmp")
        ...
    Case tFile.EndsWith("MSSlave.tmp")
        ...
End Select

Having multiple choices on the same line would be of not much difference:

Select Case True
    Case tFile.EndsWith("example 1"), tFile.EndsWith("example 2")
        ...
    Case tFile.EndsWith("example 3"), tFile.EndsWith("example 4")
        ...
End Select

If you already have a list of choices in an array/list/collection, you can also use

Dim choices1 = New String() {"example 1", "example 2"}
Dim choices2 = New String() {"example 3", "example 4"}

Select Case True
    Case choices1.Any(Function(s) tFile.EndsWith(s))
        ...
    Case choices2.Any(Function(s) tFile.EndsWith(s))
        ...
End Select

Or do the same inline if you prefer:

Select Case True
    Case (New String() {"example 1", "example 2"}).Any(Function(s) tFile.EndsWith(s))
        ...
    Case (New String() {"example 3", "example 4"}).Any(Function(s) tFile.EndsWith(s))
        ...
End Select

Your first post was exactly what I needed. – Ccorock Oct 19 '12 at 20:03 — Ccorock, Oct 19 '12 at 20:03

score 0 · Answer 2 · answered Oct 19 '12 at 19:49

The only difference between the 2 cases is the appending of the sbSubreport item. That is the only item which needs a special check and can be done like the following

Dim master = tFile.EndsWith("MSMaster.tmp")
Dim slave = tFile.EndsWith("MSSlave.tmp")
If master OrElse slave Then
    sbExisting.AppendLine(Report.sbStart.ToString)
    sbExisting.AppendLine(Report.sbHeaders.ToString)
    sbExisting.AppendLine(Report.sbItems.ToString)
    If master Then
        sbExisting.AppendLine(Report.sbSubreport.ToString)
    End If
    sbExisting.AppendLine(Report.sbEnd.ToString)
    sbExisting.AppendLine(Report.sbCol.ToString)
End If

The code is only a prototype to the actual project. This solution would only work for the specific circumstance. Interesting all the same. — Ccorock, Oct 19 '12 at 19:51

Select Case with Function EndsWith()

2 Answers2