Erro on VB "Expecting an existing scalar var"

Question

I was trying to make an function using vb. This function is to collect data for a report. Follows the example:

Public Function HeaderData() As String
Dim dados As String
dados = ""  
If Not(frm.FormQuery.FieldByName("A").AsString  = "S" And _
     frm.FormQuery.FieldByName("B").AsString  = "S" And _
     frm.FormQuery.FieldByName("C").AsString  = "S" And _
     frm.FormQuery.FieldByName("D").AsString  = "S") Then

dados = dados + "Type: "

If frm.FormQuery.FieldByName(A).AsString = "S" Then
  dados = dados + "A"
End If

If frm.FormQuery.FieldByName(B).AsString = "S" Then
  If frm.FormQuery.FieldByName(A).AsString = "S" Then
    dados = dados + ", "
  End If
  dados = dados + "B"
End If

If frm.FormQuery.FieldByName(C).AsString = "S" Then
  If frm.FormQuery.FieldByName(A).AsString = "S" Or _
     frm.FormQuery.FieldByName(B).AsString = "S" Then
     dados = dados + ", "
  End If
  dados = dados + "C"
End If

 If frm.FormQuery.FieldByName(D).AsString = "S" Then
  If frm.FormQuery.FieldByName(A).AsString = "S" Or _
     frm.FormQuery.FieldByName(B).AsString = "S" Or _
     frm.FormQuery.FieldByName(C).AsString = "S" Then
     dados = dados + ", "
  End If
  dados = dados + "D"
End If

dados =  dados + "; "

And this function causes the error: Expecting an existing scalar var.

I did other functions with the same purpose, with similar code, using the same variable to collect the data (dados) and did not cause the error. What could be happening?

The code you posted is missing an End Function and a Return statement. Is it only a copy and paste error? — sblandin, Jun 19 '15 at 13:55
**1.** Unclear what you're asking (where exactly is the exception thrown, and is that the exact exception message?), **2.** contains syntax errors (e.g. `FieldByName(D).`, i.e. missing double quotes), and **3.** non-reproducible error (what is `FormQuery`, what "fields" is it guaranteed to contain, what is the definition of `.FieldByName(…)` or `.AsString`; can they throw exceptions?) I'm voting to close (but will retract the close vote once these issues have been addressed). — stakx - no longer contributing, Jun 19 '15 at 13:57
Just correcting: In the same function I did similar conditions to the above mentioned. — Augusto Ferbonink, Jun 19 '15 at 14:03
I do not know which line is the exception, because the code editor that I'm using does not show it — Augusto Ferbonink, Jun 19 '15 at 14:05
So just to be clear, the "error" is a compile-time error, not an exception thrown at run-time? The compiler will still indicate a rough location for the error; use a reasonable IDE or run the compiler from the command line and check its output. — stakx - no longer contributing, Jun 19 '15 at 14:09
At the beginning you do FieldByName("A") than you do FieldByName(A). This is confusing and might be thesource of your problem. You should at least give us the line with the error. — the_lotus, Jun 19 '15 at 14:10
Hey guys, is solved, was missing a double quotes... Feeling an jackass for not realizing it, I reviewed the code several times I did not realize it. Sorry and thanks — Augusto Ferbonink, Jun 19 '15 at 14:12

score 0 · Answer 1 · answered Jun 19 '15 at 14:15

Your logic doesn't make much sense. I highly suggest that you write just a few lines and debug. Make sure everything works properly and than write a few more lines. Writing to much at the beginning will cause trouble.

    Dim possibleFields As String() = {"A", "B", "C", "D"}
    Dim foundFields As New List(Of String)
    Dim dados As String = ""

    For Each field As String In possibleFields
        If frm.FormQuery.FieldByName(field).AsString = "S" Then
            foundFields.Add(field)
        End If
    Next

    If foundFields.Count > 0 Then
        dados = String.Format("Type: {0}; ", String.Join(", ", foundFields.ToArray()))
    End If

Erro on VB "Expecting an existing scalar var"

1 Answers1