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DataGridView.RowPrePaint Event

Definition

Occurs before a DataGridViewRow is painted.

public:
 event System::Windows::Forms::DataGridViewRowPrePaintEventHandler ^ RowPrePaint;
public event System.Windows.Forms.DataGridViewRowPrePaintEventHandler RowPrePaint;
public event System.Windows.Forms.DataGridViewRowPrePaintEventHandler? RowPrePaint;
member this.RowPrePaint : System.Windows.Forms.DataGridViewRowPrePaintEventHandler 
Public Custom Event RowPrePaint As DataGridViewRowPrePaintEventHandler 

Event Type

Examples

The following code example demonstrates how to use a handler for the RowPrePaint event to paint a gradient row background if the row is selected. This example is part of a larger example available in How to: Customize the Appearance of Rows in the Windows Forms DataGridView Control.

// Paints the custom selection background for selected rows.
void dataGridView1_RowPrePaint(object sender,
        DataGridViewRowPrePaintEventArgs e)
{
    // Do not automatically paint the focus rectangle.
    e.PaintParts &= ~DataGridViewPaintParts.Focus;

    // Determine whether the cell should be painted
    // with the custom selection background.
    if ((e.State & DataGridViewElementStates.Selected) ==
                DataGridViewElementStates.Selected)
    {
        // Calculate the bounds of the row.
        Rectangle rowBounds = new Rectangle(
            this.dataGridView1.RowHeadersWidth, e.RowBounds.Top,
            this.dataGridView1.Columns.GetColumnsWidth(
                DataGridViewElementStates.Visible) -
            this.dataGridView1.HorizontalScrollingOffset + 1,
            e.RowBounds.Height);

        // Paint the custom selection background.
        using (Brush backbrush =
            new System.Drawing.Drawing2D.LinearGradientBrush(rowBounds,
                this.dataGridView1.DefaultCellStyle.SelectionBackColor,
                e.InheritedRowStyle.ForeColor,
                System.Drawing.Drawing2D.LinearGradientMode.Horizontal))
        {
            e.Graphics.FillRectangle(backbrush, rowBounds);
        }
    }
}
' Paints the custom selection background for selected rows.
Sub dataGridView1_RowPrePaint(ByVal sender As Object, _
    ByVal e As DataGridViewRowPrePaintEventArgs) _
    Handles dataGridView1.RowPrePaint

    ' Do not automatically paint the focus rectangle.
    e.PaintParts = e.PaintParts And Not DataGridViewPaintParts.Focus

    ' Determine whether the cell should be painted with the 
    ' custom selection background.
    If (e.State And DataGridViewElementStates.Selected) = _
        DataGridViewElementStates.Selected Then

        ' Calculate the bounds of the row.
        Dim rowBounds As New Rectangle( _
            Me.dataGridView1.RowHeadersWidth, e.RowBounds.Top, _
            Me.dataGridView1.Columns.GetColumnsWidth( _
            DataGridViewElementStates.Visible) - _
            Me.dataGridView1.HorizontalScrollingOffset + 1, _
            e.RowBounds.Height)

        ' Paint the custom selection background.
        Dim backbrush As New _
            System.Drawing.Drawing2D.LinearGradientBrush(rowBounds, _
            Me.dataGridView1.DefaultCellStyle.SelectionBackColor, _
            e.InheritedRowStyle.ForeColor, _
            System.Drawing.Drawing2D.LinearGradientMode.Horizontal)
        Try
            e.Graphics.FillRectangle(backbrush, rowBounds)
        Finally
            backbrush.Dispose()
        End Try
    End If

End Sub

Remarks

You can handle this event alone or in combination with the RowPostPaint event to customize the appearance of rows in the control. You can paint entire rows yourself, or paint specific parts of rows and use the following methods of the DataGridViewRowPrePaintEventArgs class to paint other parts:

You can also use the VisualStyleRenderer class to paint standard controls using the current theme. For more information, see Rendering Controls with Visual Styles. If you are using Visual Studio 2005, you also have access to a large library of standard images that you can use with the DataGridView control.

For more information about how to handle events, see Handling and Raising Events.

Applies to

See also