DataGridView 的重绘
.net Winform 中的DataGridView 的外观有点难看。下面是重绘DataGridView的方法，可以重绘时参考：
1.重绘DataGridView
protected override void Paint(
Graphics graphics,
Rectangle clipBounds,
Rectangle cellBounds,
int rowIndex,
DataGridViewElementStates cellState,
object value,
object formattedValue,
string errorText,
DataGridViewCellStyle cellStyle,
DataGridViewAdvancedBorderStyle advancedBorderStyle,
DataGridViewPaintParts paintParts)
{
// Call the base class method to paint the default cell appearance.
base.Paint(graphics, clipBounds, cellBounds, rowIndex, cellState,
value, formattedValue, errorText, cellStyle,
advancedBorderStyle, paintParts);
// Retrieve the client location of the mouse pointer.
Point cursorPosition =
this.DataGridView.PointToClient(Cursor.Position);
// If the mouse pointer is over the current cell, draw a custom border.
if (cellBounds.Contains(cursorPosition))
{
Rectangle newRect = new Rectangle(cellBounds.X + 1,
cellBounds.Y + 1, cellBounds.Width - 4,
cellBounds.Height - 4);
graphics.DrawRectangle(Pens.Red, newRect);
}
}
2.重绘DataGridView 的头部
protected override void OnCellPainting(DataGridViewCellPaintingEventArgs e)
{
base.OnCellPainting(e);
if (e.ColumnIndex == -1 && e.RowIndex == -1)
{
using (LinearGradientBrush brush = new LinearGradientBrush(e.CellBounds, Color.LightGray,
Color.White, LinearGradientMode.ForwardDiagonal))
{
e.Graphics.FillRectangle(brush, e.CellBounds);
Rectangle border = e.CellBounds;
border.Offset(new Point(-1, -1));
e.Graphics.DrawRectangle(Pens.Gray, border);
}
e.PaintContent(e.CellBounds);
e.Handled = true;
}
else if (e.RowIndex == -1)
{
//标题行
using (LinearGradientBrush brush = new LinearGradientBrush(e.CellBounds, Color.LightGray,
Color.White, LinearGradientMode.Vertical))
{
e.Graphics.FillRectangle(brush, e.CellBounds);
Rectangle border = e.CellBounds;
border.Offset(new Point(-1, -1));
e.Graphics.DrawRectangle(Pens.Gray, border);
}
e.PaintContent(e.CellBounds);
e.Handled = true;
}
else if (e.ColumnIndex == -1)
{
//标题列
using (LinearGradientBrush brush = new LinearGradientBrush(e.CellBounds, Color.LightGray,
Color.White, LinearGradientMode.Horizontal))
{
e.Graphics.FillRectangle(brush, e.CellBounds);
Rectangle border = e.CellBounds;
border.Offset(new Point(-1, -1));
e.Graphics.DrawRectangle(Pens.Gray, border);
}
e.PaintContent(e.CellBounds);
e.Handled = true;
}
}
3.重绘实现合并单元格
#region"合并单元格的测试"
private int? nextrow = null;
private int? nextcol = null;
private void dataGridView1_CellFormatting(object sender, System.Windows.Forms.DataGridViewCellFormattingEventArgs e)
{
if (this.dataGridView1.Columns["description"].Index == e.ColumnIndex && e.RowIndex >= 0)
{
if (this.nextcol != null & e.ColumnIndex == this.nextcol)
{
e.CellStyle.BackColor = Color.LightBlue;
this.nextcol = null;
}
if (this.nextrow != null & e.RowIndex == nextrow)
{
e.CellStyle.BackColor = Color.LightPink;
this.nextrow = null;
}
if (e.RowIndex != this.dataGridView1.RowCount - 1)
{
if (e.Value.ToString() == this.dataGridView1.Rows[e.RowIndex + 1].Cells[e.ColumnIndex].Value.ToString())
{
e.CellStyle.BackColor = Color.LightPink;
nextrow = e.RowIndex + 1;
}
}
}
if (this.dataGridView1.Columns["name"].Index == e.ColumnIndex && e.RowIndex >= 0)
{
if (e.Value.ToString() == this.dataGridView1.Rows[e.RowIndex].Cells[e.ColumnIndex + 1].Value.ToString())
{
e.CellStyle.BackColor = Color.LightBlue;
nextcol = e.ColumnIndex + 1;
}
}
}
//==========================
//绘制单元格
private void dataGridView1_CellPainting(object sender, System.Windows.Forms.DataGridViewCellPaintingEventArgs e)
{
//纵向合并
if (this.dataGridView1.Columns["description"].Index == e.ColumnIndex && e.RowIndex >= 0)
{
using (
Brush gridBrush = new SolidBrush(this.dataGridView1.GridColor),
backColorBrush = new SolidBrush(e.CellStyle.BackColor))
{
using (Pen gridLinePen = new Pen(gridBrush))
{
// 擦除原单元格背景
e.Graphics.FillRectangle(backColorBrush, e.CellBounds);
////绘制线条,这些线条是单元格相互间隔的区分线条,
////因为我们只对列name做处理,所以datagridview自己会处理左侧和上边缘的线条
if (e.RowIndex != this.dataGridView1.RowCount - 1)
{
if (e.Value.ToString() != this.dataGridView1.Rows[e.RowIndex + 1].Cells[e.ColumnIndex].Value.ToString())
{
e.Graphics.DrawLine(gridLinePen, e.CellBounds.Left, e.CellBounds.Bottom - 1,
e.CellBounds.Right - 1, e.CellBounds.Bottom - 1);//下边缘的线
//绘制值
if (e.Value != null)
{
e.Graphics.DrawString((String)e.Value, e.CellStyle.Font,
Brushes.Crimson, e.CellBounds.X + 2,
e.CellBounds.Y + 2, StringFormat.GenericDefault);
}
}
}
else
{
e.Graphics.DrawLine(gridLinePen, e.CellBounds.Left, e.CellBounds.Bottom - 1,
e.CellBounds.Right - 1, e.CellBounds.Bottom - 1);//下边缘的线
//绘制值
if (e.Value != null)
{
e.Graphics.DrawString((String)e.Value, e.CellStyle.Font,
Brushes.Crimson, e.CellBounds.X + 2,
e.CellBounds.Y + 2, StringFormat.GenericDefault);
}
}
//右侧的线
e.Graphics.DrawLine(gridLinePen, e.CellBounds.Right - 1,
e.CellBounds.Top, e.CellBounds.Right - 1,
e.CellBounds.Bottom - 1);
e.Handled = true;
}
}
}
//横向合并
if (this.dataGridView1.Columns["name"].Index == e.ColumnIndex && e.RowIndex >= 0)
{
using (
Brush gridBrush = new SolidBrush(this.dataGridView1.GridColor),
backColorBrush = new SolidBrush(e.CellStyle.BackColor))
{
using (Pen gridLinePen = new Pen(gridBrush))
{
// 擦除原单元格背景
e.Graphics.FillRectangle(backColorBrush, e.CellBounds);
if (e.Value.ToString() != this.dataGridView1.Rows[e.RowIndex].Cells[e.ColumnIndex + 1].Value.ToString())
{
//右侧的线
e.Graphics.DrawLine(gridLinePen, e.CellBounds.Right - 1, e.CellBounds.Top,
e.CellBounds.Right - 1, e.CellBounds.Bottom - 1);
//绘制值
if (e.Value != null)
{
e.Graphics.DrawString((String)e.Value, e.CellStyle.Font,
Brushes.Crimson, e.CellBounds.X + 2,
e.CellBounds.Y + 2, StringFormat.GenericDefault);
}
}
//下边缘的线
e.Graphics.DrawLine(gridLinePen, e.CellBounds.Left, e.CellBounds.Bottom - 1,
e.CellBounds.Right - 1, e.CellBounds.Bottom - 1);
e.Handled = true;
}
}
}
}
#endregion