I know, maybe this is a question that comes up quite often, but I haven't been able to work on it. How can I save this checkbox values in an XML file using VB.Net?
Private Sub ChkVul_Click(sender As Object, e As EventArgs) Handles ChkVul.Click
If ChkVul.Checked = True Then
Me.pnlInsert.Visible = True
Else
Me.pnlInsert.Visible = False
End If
End Sub
Before I provide you with an answer, I wanted to recommend a slight code change. Since you are setting the Boolean value of pnlInsert.Visible
based on a condition, which itself returns a Boolean value, simply get rid of the conditional check in the first place:
pnlInsert.Visible = ChkVul.Checked
Now to your question. What you are essentially asking is how to write a value to an XML file. Something to consider is that XML is only a markup language. At the end of the day, an XML file is simply a file that contains formatted text.
If you do not already have an XML file to read from, simply create a new instance of a XDocument ( documentation ). If you do have an XML file, then create a new instance of a XDocument by calling the static XDocument.Load method ( documentation ). Here is a function that takes in a file location and attempts to load a XDocument, if it is unable to then it returns a blank XDocument with a single <root>
element:
Private Function LoadOrCreateXml(filename As String) As XDocument
Dim document = New XDocument()
document.Add(New XElement("root"))
Try
If (Not String.IsNullOrWhiteSpace(filename) AndAlso IO.File.Exists(filename)) Then
document = XDocument.Load(filename)
End If
Catch ex As Exception
' for the sake of this example, just silently fail
End Try
Return document
End Function
Now that you have an XDocument, it is just a matter of writing the value. You did not provide any details as to where the value should go or what the tag name should be, so I am going to assume that it should be a child of the <root />
element and the value would look something like this: <ChkVul>true/false</ChkVul>
.
To do this, we will need to get the <root />
element by calling the Element method ( documentation ) on the XDocument to get the element and then call the Add method ( documentation ) on the resulting XElement to add our node with the value:
Dim document = LoadOrCreateXml("my-xml-file.txt")
document.Element("root").Add(New XElement("ChkVul", ChkVul.Checked))
The final piece of all this is to write the in-memory XDocument back to the file. You can leverage the XDocument.Save method ( documentation ):
Dim filename = "my-xml-file.txt"
Dim document = LoadOrCreateXml(filename)
document.Element("root").Add(New XElement("ChkVul", ChkVul.Checked))
document.Save(filename)
Maybe this is what you have in mind. I tested this with other controls,
Public Class Form1
Private SavePath As String = IO.Path.Combine(Environment.GetFolderPath(Environment.SpecialFolder.Desktop),
"MyControls.xml") 'some valid path <-----------<<<
Private Sub Form1_FormClosing(sender As Object, e As FormClosingEventArgs) Handles Me.FormClosing
SaveCheckedState(ChkVul, "ChkVul", True)
End Sub
Private Sub Form1_Shown(sender As Object, e As EventArgs) Handles Me.Shown
If IO.File.Exists(SavePath) Then
Try
MyControls = XElement.Load(SavePath)
For Each el As XElement In MyControls.Elements
Dim ctrl() As Control = Me.Controls.Find(el.@name, True)
If ctrl.Length > 0 Then
Dim chkd As System.Reflection.PropertyInfo = ctrl(0).GetType().GetProperty("Checked")
Dim chkdV As Boolean = Boolean.Parse(el.@checked)
chkd.SetValue(ctrl(0), chkdV)
End If
Next
Catch ex As Exception
'todo
End Try
End If
End Sub
Private Sub ChkVul_CheckedChanged(sender As Object, e As EventArgs) Handles ChkVul.CheckedChanged
If ChkVul.Checked Then
Me.pnlInsert.Visible = True
Else
Me.pnlInsert.Visible = False
End If
SaveCheckedState(ChkVul, "ChkVul")
End Sub
Private Sub RadioButton1_CheckedChanged(sender As Object, e As EventArgs) Handles RadioButton1.CheckedChanged
SaveCheckedState(RadioButton1, "RadioButton1")
End Sub
Private Sub CheckBox1_CheckedChanged(sender As Object, e As EventArgs) Handles CheckBox1.CheckedChanged
SaveCheckedState(CheckBox1, "CheckBox1")
End Sub
Private MyControls As XElement = <controls>
</controls>
Private Sub SaveCheckedState(Ctrl As Control,
Name As String,
Optional Save As Boolean = False)
If Ctrl.GetType().GetProperty("Checked") IsNot Nothing Then
Dim chkd As System.Reflection.PropertyInfo = Ctrl.GetType().GetProperty("Checked")
Dim chkdV As Boolean = CBool(chkd.GetValue(Ctrl))
Dim ie As IEnumerable(Of XElement)
ie = From el In MyControls.Elements
Where el.@name = Ctrl.Name
Select el Take 1
Dim thisXML As XElement
If ie.Count = 0 Then
thisXML = <ctrl name=<%= Name %>></ctrl>
MyControls.Add(thisXML)
Else
thisXML = ie(0)
End If
thisXML.@checked = chkdV.ToString
End If
If Save Then
Try
MyControls.Save(SavePath)
Catch ex As Exception
'todo
' Stop
End Try
End If
End Sub
End Class
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