BindingSource.Position Property

 

Gets or sets the index of the current item in the underlying list.

Namespace:   System.Windows.Forms
Assembly:  System.Windows.Forms (in System.Windows.Forms.dll)

<BrowsableAttribute(False)>
Public Property Position As Integer

Property Value

Type: System.Int32

A zero-based index that specifies the position of the current item in the underlying list.

When setting the Position property, out-of-range values are treated in the following manner:

  • Negative values are treated as 0.

  • Values greater than or equal to Count are treated as Count minus 1.

Changing the Position property will adjust the Current property likewise.

The following code example demonstrates the MoveNext, MoveFirst, Current, and Position members. To run this example, paste the code into a form that imports the System.Drawing.Drawing2D namespace and contains a BindingSource named BindingSource1 and a button named button1. Associate the Form1_Load and Form1_Paint methods with the Load and Paint events for the form, and associate the button1_click method with the Click event for button1. Visual Basic users will need to add a reference to System.Data.dll.

Sub Form1_Load(ByVal sender As Object, ByVal e As EventArgs) _
    Handles Me.Load

    ' Set the data source to the Brush type and populate
    ' BindingSource1 with some brushes.
    BindingSource1.DataSource = GetType(System.Drawing.Brush)
    BindingSource1.Add(New TextureBrush(New Bitmap(GetType(Button), _
        "Button.bmp")))
    BindingSource1.Add(New HatchBrush(HatchStyle.Cross, Color.Red))
    BindingSource1.Add(New SolidBrush(Color.Blue))

End Sub



Private Sub button1_Click(ByVal sender As Object, ByVal e As EventArgs) _
     Handles button1.Click

    ' If you are not at the end of the list, move to the next item
    ' in the BindingSource.
    If BindingSource1.Position + 1 < BindingSource1.Count Then
        BindingSource1.MoveNext()

        ' Otherwise, move back to the first item.
    Else
        BindingSource1.MoveFirst()
    End If

    ' Force the form to repaint.
    Me.Invalidate()

End Sub


Sub Form1_Paint(ByVal sender As Object, ByVal e As PaintEventArgs)

    ' Get the current item in the BindingSource.
    Dim item As Brush = CType(BindingSource1.Current, Brush)

    ' If the current type is a TextureBrush, fill an ellipse.
    If item.GetType().Equals(GetType(TextureBrush)) Then
        e.Graphics.FillEllipse(item, _
        e.ClipRectangle)

        ' If the current type is a HatchBrush, fill a triangle.
    ElseIf item.GetType().Equals(GetType(HatchBrush)) Then
        e.Graphics.FillPolygon(item, New Point() _
         {New Point(0, 0), New Point(0, 200), New Point(200, 0)})

        ' Otherwise, fill a rectangle.
    Else
        e.Graphics.FillRectangle(item, e.ClipRectangle)
    End If

End Sub

.NET Framework
Available since 2.0
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