[RESOLVED] [2005] Reverse the process.

[noahssite]

Hello below is a sub that writes a bunch of information to a file.
Basicly it is in a way a 'save' method for my application. I now want to create a 'load' so to do this i will have to reverse this process, how may i do this? Note that since i am recording info through a for each loop the loops and the means of how information is retrieved must be in the same order.

Here is my code:

'Here:
Private Sub AddCustomer()
        Dim Customer_Info As New List(Of String)
        For Each ctrl As Control In Me.CustomerEditArea.Controls
            If Not (TypeOf (ctrl) Is Label) And Not (TypeOf (ctrl) Is CheckBox) And Not (TypeOf (ctrl) Is DateTimePicker) Then
                Customer_Info.Add(ctrl.Text.Trim)
            End If
        Next
        Customer_Info.Add(DateSelecter.Value.ToString)
        For Each chk As CheckBox In Me.CustomerEditArea.Controls
            If TypeOf (chk) Is CheckBox Then
                Customer_Info.Add(chk.CheckState.ToString)
            End If
        Next
        Customer_Info.Add(lblsubtotal.Text)
        Customer_Info.Add(lbltotal.Text)
        IO.File.WriteAllLines(ProfileDirectory & txtfirstname.Text.Trim & txtlastname.Text.Trim & ".ERcr", Customer_Info.ToArray)
    End Sub

[obi1kenobi]

First of all, I'd suggest that you try XML serialization, it should solve many of your worries with one stroke.

If you decide to stick with this method, try this:

Dim filepath As String '= file path here
Dim lines() As String = IO.File.ReadAllLines(filepath)
Dim i As Integer
For Each ctrl As Control In Me.CustomerEditArea.Controls
     If Not (TypeOf (ctrl) Is Label) And Not (TypeOf (ctrl) Is CheckBox) And Not (TypeOf (ctrl) Is DateTimePicker) Then
          ctrl.Text = lines(i)
          i += 1
     End If
Next
For Each chk As CheckBox In Me.CustomerEditArea.Controls
     If TypeOf (chk) Is CheckBox Then
          chk.CheckState = CType(lines(i), CheckState)    'This line will work for sure if you change the chk.CheckState.ToString to a CStr(chk.CheckState), otherwise I'm not sure
          'If it doesn't and you don't want to change your code, you'll need to insert a Select Case block
          i += 1
     End If
Next
lblsubtotal.Text = lines(i)
lbltotal.Text = lines(i+1)

If the code above doesn't work, post the exception and I'll do my best to fix it.

[noahssite]

In the code you supplied you are missing line 9 of my code:

Customer_Info.Add(DateSelecter.Value.ToString)

How would i place that in? (between the first and second for each loop)

[obi1kenobi]

Hmmm... Is DateSelecter a DateTimePicker? I'm not exactly sure which date format will the ToString method return, that should be checked, but you'd use Date.Parse and set it to the Value property I think... Unfortunately, I haven't used a DateTimePicker and I have no idea which format will be used in ToString, as for some reason I cannot open the MSDN webpage... :S I'll try again in the morning, I need to get some sleep now...

Btw, this is exactly why I suggested using XML serialization... When serializing a class or structure, you'd keep a String as a String, a Date as a Date, an Enum as that same Enum and a List(Of T) as a List(Of T). You'd only have to worry about saving the data in the class and retrieving and using it afterwards...

[noahssite]

Yes it is a DateTimePicker...

Then just wondering, how would XML serialization work?

[obi1kenobi]

It would be something like this:

Public Structure Data
    Public texts As List(Of String)
    Public checkboxes As List(Of CheckState)
    Public dt As Date
    Public total As String
    Public subtotal As String
End Structure

'You'd populate an instance of this structure and then:
Public Sub Serialize(ByVal data As Data)
    Dim serializer As New Xml.Serialization.XmlSerializer(GetType(data)))
    Dim fs As New IO.FileStream("test.xml", IO.FileMode.Create)
    serializer.Serialize(fs, items)
    fs.Close()
End Sub

'When you want to recover the data:
Public Function Deserialize() As Data
    Dim dat As Data
    Dim serializer As New Xml.Serialization.XmlSerializer(GetType(data)))
    Dim sReader As New IO.StreamReader("test.xml")
    dat = DirectCast(serializer.Deserialize(sReader), Data)
    sReader.Close()
    Return dat
End Function

You can also serialize a class instance, not only a structure. The only prerequisite is that the types you use must have parameterless constructors.

[obi1kenobi]

So how do you like it? Have you decided on what to use?

[noahssite]

I think i might stick to post #2. Since it seems easier and works better with my code.

[obi1kenobi]

As you wish. Then use the following to store and retrieve the date:

'This will give you the date as a String
Dim dat As New Date = Date.Now 
dat.ToString(CultureInfo.InvariantCulture)

'And this will convert it back to a DateTime
Dim dateString As String = "5/1/2008 8:30:52 AM"
Dim dat As Date = Date.Parse(dateString, CultureInfo.InvariantCulture)

[noahssite]

Thanks

[obi1kenobi]

Anytime Glad to be able to help

[noahssite]

if i were to write the dateselector.value on the first line then for loading couldnt i do this?

DateSelecter.Value = (Date.Parse(lines(0)))

Since for this one program i am using VS 2005 and Culture.. doesnt exist unless i have to import something..

[obi1kenobi]

It's System.Globalization.Culture and it's an assembly from .Net 2.0 so it must exist in VS 2005.

[noahssite]

ok ill check it, but just wondering then what i wrote will that work to or it will result in error?