How do I add string to an array x2 and the get it back?

Question

Essentially what I am trying to do is write a program where you input the person's name and their date of birth, store them to an array (note sure if I have to do two separate arrays) and then by entering their name into another text box and clicking another button I can get the date of birth back.

I know I have to include an if-loop, I know how to declare an array.

I am guessing that I maybe need to use a select case.

Here is the code:

Public Class Form1
Dim Name(5) As String
Dim DOB(5) As String
Dim i As Integer
Private Sub btnNameEnter_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles btnNameEnter.Click

    Name(i) = txtInputName.Text
    DOB(i) = txtInputDOB.Text

    If i = 6 Then
        MsgBox("You cannot enter any more names.")
    End If

    For i = 1 To 5
        Name(i) = i
        txtInputName.Clear()
        txtInputDOB.Clear()
    Next i

End Sub

Private Sub btnFindDOB_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles btnFindDOB.Click
    Select Case Name(i)
        Case Is Name(1)
            MsgBox("Date of birth: " & DOB(1))
        Case is Name(2)
            MsgBox("Date of birth: " & DOB(2))
        Case is Name(3)
            MsgBox("Date of birth: " & DOB(3))
        Case is Name(4)
            MsgBox("Date of birth: " & DOB(4))
        Case is Name(5)
            MsgBox("Date of birth: " & DOB(5))

    End Select
End Sub
End Class

I would show a picture of the program but visual basic keeps deleting it for some reason and doesn't let me re add the buttons.

Here is an image of the error list: http://gyazo.com/2489a307f4a8e2d9ce65aa2ad79b04f1 ScreenShot-error-list )

Public Class Form1 Dim DOB(5) As String Dim i As Integer Private Sub btnEnter_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles btnEnter.Click Dim Name(5) As String

    Dim Counter As Integer
    txtNameInp.Text = Name(i)
    txtDOBInput.Text = DOB(i)

    Counter = 0

    For i = 1 To 5
        If Counter = 6 Then
            MsgBox("You can only enter 5 names and DOBs")
        End If
        Name(i) = txtNameInp.Text
        DOB(i) = txtDOBInput.Text
        Counter = Counter + 1
    Next i
End Sub

Private Sub btnFindDOB_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles btnFindDOB.Click
    Select Case Name(i)
        Case Name(1)
            MsgBox(DOB(1))
        Case Name(2)
            MsgBox(DOB(2))
        Case Name(3)
            MsgBox(DOB(3))
        Case Name(4)
            MsgBox(DOB(4))
        Case Name(5)
            MsgBox(DOB(5))
    End Select
End Sub

End Class

Here's an error: http://gyazo.com/487290c3e523003fe58f82a15fdf6faa - this one occurs when I try and enter the second number

Ňɏssa Pøngjǣrdenlarp Ňɏssa Pøngjǣrdenlarp · Accepted Answer · 2014-10-15T18:05:38

It is hard to be to precise using a picture of the errors instead of comments in the code indicating the location and text of the error, but from what I can see:

Forms already have a Name property and you are trying to redefine it via your array. use something like myNames instead.
You have a module level variable named i and a local one as well. Change the global one to something useful like curPosition. This will track with element you are currently storing to.
If you want to stop adding to the array at 6 you need to do so in code. Add Exit Sub after the MsgBox; you want to do this before you store anything to the arrays, not after. Maybe add a message saying - 'now I will tell you the DOB for a name`.
If you want to be clever (doubtful) have both a 'Guess Name' and Guess DOB button on the form and report the Name for a given DOB. Its basically the same code.
the button enter code will run every time they click so you do not need a loop. This is plain nonsense by the way: Name(i) = i you are overwriting everything with whatever i happens to be. Just add to myNames and myDOB using curPosition as the index and then increment it:

myNames(curPosition) = txtInputName.Text
The relational error is from this: Case Is Name(1)

The error is telling you that it expects a relational operator, which Is is not (Is is used with Objects, which a string is not). The code is also a bit wonky here because you are not controlling the value if i. To compare txtInputName:

Select Case txtInputName.Text   
    Case = Name(1)       ' ie does txtInputName match the value in Name(1)?
      ...

- Rather than a case statement, you could use a For Loop here for less code.

Lets learn about classes. Rather than arrays which will dissociate related pieces of info from each other a class will keep the data together.

Public Class Person

    Public property Name As String
    Public Property DOB As DateTime       ' I refuse to store a Date as string

    Public Sub New(sName as String, dt as DateTime)
       Name = sName
       DOB = dt
    End Sub
End Class

Next, a nifty list to hold some person objects. A list is like an array but smarter:

Private pList As New List(Of Person)

Add a person:

' ToDo: check that the date is valid using TryParse instead
' this exercise is left to the student
Dim p As New Person(txtInputName.Text, Datetime.Parse(txtInputDOB.Text))
plist.Add(p)

Find a person:

' case insensitive search
Dim search As String = txtNameToFind.Text.ToLowerInvariant

For Each p as Person In pList
    If P.Name.TolowerInvariant = search Then
        txtDOB.Text = p.DOB.ToString
        Exit For
    End If
Next

How do I add string to an array x2 and the get it back?

2 Answers