最近把我们的b/s系统,增加智能客户端的功能。确实智能客户端是非常好用的东西。可惜winform的控件功能不怎么强大,相比vb差很多啊。比如DataGridView不支持二维表头,不支持表尾合计,相比之下 web的好办多了（还是喜欢Web的排版、导航，但喜欢Win的操作性，希望WPF早日流行）。
但是 MIS系统没有二维表头确实是客户不能接受的,尝试了com控件flexgrid或者开源的SourceGrid3，但都不怎么好用,于是想改造一下DataGridView。我的做法是在CellPainting做手脚。花了一天时间尝试，只是做出原型，还没有完善，希望有需要的朋友少走弯路。
1,继承DataGridView，添加表头信息类。
2，添加CellPainting，代码如下：
private void DataGridViewEx_CellPainting(object sender, DataGridViewCellPaintingEventArgs e)
{
if (e.RowIndex == -1)
{
// int w = dataGridView1.HorizontalScrollingOffset + dataGridView1.TopLeftHeaderCell.Size.Width + dataGridView1.Columns[0].Width + 10;
Rectangle newRect = new Rectangle(e.CellBounds.X + 1,
e.CellBounds.Y + 1, e.CellBounds.Width - 4,
e.CellBounds.Height - 4);
using (
Brush gridBrush = new SolidBrush(this.GridColor),
backColorBrush = new SolidBrush(e.CellStyle.BackColor))
{
using (Pen gridLinePen = new Pen(gridBrush))
{
// Erase the cell.
e.Graphics.FillRectangle(backColorBrush, e.CellBounds);
// Draw the grid lines (only the right and bottom lines;
// DataGridView takes care of the others).
e.Graphics.DrawLine(gridLinePen, e.CellBounds.Left,
e.CellBounds.Bottom - 1, e.CellBounds.Right - 1,
e.CellBounds.Bottom - 1);
if (e.ColumnIndex > -1 && topRow!=null&&topRow.Cells[e.ColumnIndex].ColSpan>1)
{
e.Graphics.DrawLine(gridLinePen, e.CellBounds.Right - 1,
e.CellBounds.Top + e.ClipBounds.Height / 2, e.CellBounds.Right - 1,
e.CellBounds.Bottom);
}
else
{
e.Graphics.DrawLine(gridLinePen, e.CellBounds.Right - 1,
e.CellBounds.Top, e.CellBounds.Right - 1,
e.CellBounds.Bottom);
}
// Draw the inset highlight box.
// e.Graphics.DrawRectangle(Pens.Blue, newRect);
int scale = e.CellBounds.Height/3;
if (e.ColumnIndex > -1 && topRow.Cells[e.ColumnIndex].Text != null)
{
scale= e.CellBounds.Height / 2;
e.Graphics.DrawLine(gridLinePen, e.CellBounds.Left, e.CellBounds.Bottom - e.CellBounds.Height / 2, e.CellBounds.Right, e.CellBounds.Bottom - e.CellBounds.Height / 2);
}
// Draw the text content of the cell, ignoring alignment.
if (e.Value != null)
{
e.Graphics.DrawString(e.Value.ToString(), e.CellStyle.Font,
Brushes.Crimson, e.CellBounds.X + 2,
e.CellBounds.Y + scale+ 2, StringFormat.GenericDefault);
}
if (e.ColumnIndex > -1 && topRow.Cells[e.ColumnIndex].RelateIndex > -1 && topRow.Cells[e.ColumnIndex].Text!=null)
{
Rectangle recCell = new Rectangle(e.CellBounds.X - 1 - topRow.Cells[e.ColumnIndex].SpanRowWith,
e.CellBounds.Y + 1, topRow.Cells[e.ColumnIndex].SpanRowWith,
e.CellBounds.Height / 2);
StringFormat sf = new StringFormat();
sf.Alignment = StringAlignment.Center;
e.Graphics.DrawString(topRow.Cells[e.ColumnIndex].Text, e.CellStyle.Font, Brushes.Crimson, recCell, sf);
}
e.Handled = true;
}
}
}
}3，调用方法
dataGridViewEx1.TopRow.Cells[2].Text = "入库";
dataGridViewEx1.TopRow.Cells[2].ColSpan = 2;
dataGridViewEx1.TopRow.Cells[4].Text = "出库";
dataGridViewEx1.TopRow.Cells[4].ColSpan = 2;
4，效果图
至于表尾合计，也做出了原型。二维表头+表尾合计，基本上满足需求了。