How do I handle this

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G

Guest

i have
Public Function ShowMyDate(ByVal dtmDate As Date, ByVal bytDate As Short) As
String

I get an error if the combobox is "". Which will lead me into the next
question

Me.Label7.Text = i.ShowMyDate(Date.Today(), Me.ComboBox2.Text) in a form

Where can i find info on custom errors?

Brian
 
Brian said:
I get an error if the combobox is "". Which will lead me into the next
question
Click to expand...

Are we supposed to guess what the error is? Inside your method, you
will have to check that the arguments supplied are not blank or null
(whichever is appropriate for your case).
Where can i find info on custom errors?
Click to expand...

Generally speaking, you would create a class derived from
ApplicationException and then throw a new instance of that class when
needed.
 
Why can you not check that value of the combo is not ""

Generally if you add Try, Catch block you can get error info

hth,
Samuel
 
Brian said:
i have
Public Function ShowMyDate(ByVal dtmDate As Date, ByVal bytDate As Short) As
String

I get an error if the combobox is "". Which will lead me into the next
question

Me.Label7.Text = i.ShowMyDate(Date.Today(), Me.ComboBox2.Text) in a form

Where can i find info on custom errors?

Brian
Click to expand...
It would help if we knew what your function is doing, and why the second
parameter is a short, and what the error is.

T
 
i have
Public Function ShowMyDate(ByVal dtmDate As Date, ByVal bytDate As
Short) As
String
I get an error if the combobox is "". Which will lead me into the
next question

Me.Label7.Text = i.ShowMyDate(Date.Today(), Me.ComboBox2.Text) in a
form
Click to expand...

Your ShowMyDate function is requiring a Short for the second parameter, but
you are passing a string (me.combobox2.text). If you turn Option Strict On,
this should become apparent at compile time rather than runtime. Additionally,
you should always evaulate the validity of the parameters coming into your
method to make sure the right type is being passed. Consider the following:

public Function FormatFoo(ByVal foo as string) as string
Return foo.ToUpper
end function

This method would fail if you pass it Nothing (which is possible if you send
it the value of me.ComboBox2.Text when no value is selected). It is better
to do the following:

public Function FormatFoo(ByVal foo as string) as string
if foo.IsNullOrEmpty then
Return String.Empty
else
Return foo.ToUpper
end if
end function

In your case, I would recommend you evaluate dtmDate and bytDate to make
sure they are not Nothing before trying to use them.
Where can i find info on custom errors?
Click to expand...

Search (using your favorite search engine) "custom exception". Be aware that
the recommendation has moved from inheriting from ApplicationException toward
inheriting from Exception.

Jim Wooley
http://devauthority.com/blogs/jwooley/default.aspx
 
ok, I could have been a bit more spicfic... here is my code in the form
class....(running from my form)
Private Sub Button2_Click(ByVal sender As System.Object, ByVal e As
System.EventArgs) Handles Button2.Click
Dim i As GSCSchedule.Schedules = New GSCSchedule.Schedules
Try

Me.Label2.Text = i.ShowTeamKU(Date.Today(), Me.ComboBox1.Text)
Catch ex As GSCExceptions
MessageBox.Show(ex.Message)
Catch ex As Exception

End Try
i = Nothing

End Sub

Private Sub Button3_Click(ByVal sender As System.Object, ByVal e As
System.EventArgs) Handles Button3.Click
Dim i As GSCSchedule.Schedules = New GSCSchedule.Schedules
Try

Me.Label7.Text = i.ShowTeamUT(Date.Today(), Me.ComboBox2.Text)
Catch ex As GSCExceptions
MessageBox.Show(ex.Message)
Catch ex As Exception
'MessageBox.Show(ex.Message)
End Try
i = Nothing
End Sub

the show teams function is a dll and in that class is...
Public Function ShowTeamKU(ByVal dtmDate As Date, ByVal strTeam As
String) As String
Dim result As String = ""
Dim strScheduled As String = ""

Select Case strTeam.ToUpper
Case Is = "A"
result = ShiftSchedule_28(dtmDate).Substring(0, 1)
Case Is = "B"
result = ShiftSchedule_28(dtmDate).Substring(1, 1)
Case Is = "C"
result = ShiftSchedule_28(dtmDate).Substring(2, 1)
Case Is = "D"
result = ShiftSchedule_28(dtmDate).Substring(3, 1)
Case Else
Throw New GSCExceptions(strTeam.ToUpper)
End Select
end function

Public Function ShowTeamUT(ByVal dtmDate As Date, ByVal bytTeam As
Short) As String
Dim result As String = ""
Dim strScheduled As String = ""

Select Case bytTeam
Case Is = 1
result = ShiftSchedule_35(dtmDate).Substring(0, 1)
Case Is = 2
result = ShiftSchedule_35(dtmDate).Substring(1, 1)
Case Is = 3
result = ShiftSchedule_35(dtmDate).Substring(2, 1)
Case Is = 4
result = ShiftSchedule_35(dtmDate).Substring(3, 1)
Case Is = 5
result = ShiftSchedule_35(dtmDate).Substring(4, 1)
Case Else
Throw New GSCExceptions(bytTeam)

End Select
end function

AND IN MY error trapping class...

Public Class GSCExceptions
Inherits ApplicationException

Private _strTeam As String
Private _intTeam As Short

Public ReadOnly Property strTeam() As String
Get
Return _strTeam
End Get
End Property

Public ReadOnly Property intTeam() As Short
Get
Return _intTeam
End Get
End Property

Public Sub New(ByVal Team As String)
MyBase.New("Team '" & Team & "' does not exist")
_strTeam = Team
End Sub
Public Sub New(ByVal Team As Short)
MyBase.New("Team bb'" & Team & "' does not exist")
_intTeam = Team
End Sub

End Class

when I was calling the code to run the function with the combobox and
passing ""
I would get a covert from string to integer error.... which was outside of
dll. Silly me, had a brain cramp... I should know that form error checking
should be done their. I am just learning DotNet, so you'll get questions
like this from me from time to time. ...
 
Brian,

As a lot is said, one little addition.

If you need to pass string as well as short, than you can make an overloaded
function.

(I go for the option strict on answer normally)

Cor
 
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