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DataGridViewRowPrePaintEventHandler Delegate

  • Reference

Definition

Namespace:
System.Windows.Forms
Assembly:
System.Windows.Forms.dll
Source:
DataGridViewEventHandlers.cs
Source:
DataGridViewEventHandlers.cs
Source:
DataGridViewEventHandlers.cs

Represents the method that will handle the RowPrePaint event of a DataGridView.

public delegate void DataGridViewRowPrePaintEventHandler(System::Object ^ sender, DataGridViewRowPrePaintEventArgs ^ e);
public delegate void DataGridViewRowPrePaintEventHandler(object sender, DataGridViewRowPrePaintEventArgs e);
public delegate void DataGridViewRowPrePaintEventHandler(object? sender, DataGridViewRowPrePaintEventArgs e);
type DataGridViewRowPrePaintEventHandler = delegate of obj * DataGridViewRowPrePaintEventArgs -> unit
Public Delegate Sub DataGridViewRowPrePaintEventHandler(sender As Object, e As DataGridViewRowPrePaintEventArgs)

Parameters

sender
Object

The source of the event.

e
DataGridViewRowPrePaintEventArgs

A DataGridViewRowPrePaintEventArgs that contains the event data.

Examples

The following code example presents a DataGridViewRowPrePaintEventHandler delegate that paints a gradient row background if the row is selected. This code example is part of a larger example provided 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

When you create a DataGridViewRowPrePaintEventHandler delegate, you identify the method that will handle the event. To associate the event with your event handler, add an instance of the delegate to the event. The event handler is called whenever the event occurs, unless you remove the delegate. For more information about event-handler delegates, see Handling and Raising Events.

Extension Methods

GetMethodInfo(Delegate)

Gets an object that represents the method represented by the specified delegate.

Applies to

See also