DataGridViewRowPrePaintEventHandler 委托

定义

命名空间:

System.Windows.Forms

程序集:

System.Windows.Forms.dll

表示将用来处理 RowPrePaint 的 DataGridView 事件的方法。

public delegate void DataGridViewRowPrePaintEventHandler(System::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)

参数

sender

Object

事件源。

e

DataGridViewRowPrePaintEventArgs

包含事件数据的 DataGridViewRowPrePaintEventArgs。

示例

下面的代码示例演示了一个 DataGridViewRowPrePaintEventHandler 委托，该委托在选定行时绘制渐变行背景。 此代码示例是How to： Customize the Appearance of Rows in the Windows 窗体 DataGridView 控件中提供的更大示例的一部分。

// 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

注解

创建 DataGridViewRowPrePaintEventHandler 委托时，需要标识将处理该事件的方法。 若要将事件与事件处理程序关联，请将该委托的一个实例添加到事件中。 除非移除了该委托，否则每当发生该事件时就会调用事件处理程序。 有关事件处理程序委托的详细信息，请参阅 处理和引发事件。

扩展方法

另请参阅

• DataGridView
• RowPrePaint
• 如何：自定义 Windows 窗体 DataGridView 控件中行的外观