如何正确合并DataGridView中的行HeadCell？

Question

我正在尝试合并DataGridView中的奇数行headecell，这似乎可行，但是当鼠标移到单元格上方时，它们可能坏了

代码来了，如何改进呢？谢谢！

using System;
using System.Collections.Generic;
using System.ComponentModel;
using System.Data;
using System.Drawing;
using System.Linq;
using System.Text;
using System.Windows.Forms;

namespace DGVRowHeaderCellMerge
{
    public partial class Form1 : Form
    {
        public Form1()
        {
            InitializeComponent();
            this.dataGridView1.Scroll += (s, e) => this.dataGridView1.Invalidate();
        }

        private void Form1_Load(object sender, EventArgs e)
        {

            dataGridView1.GetType().InvokeMember("DoubleBuffered", System.Reflection.BindingFlags.NonPublic | System.Reflection.BindingFlags.Instance | System.Reflection.BindingFlags.SetProperty, null, dataGridView1, new object[] { true });

            dataGridView1.EnableHeadersVisualStyles = false;

            dataGridView1.RowHeadersWidth = 160;
            dataGridView1.ColumnHeadersHeight = 40;
            dataGridView1.ColumnHeadersBorderStyle = DataGridViewHeaderBorderStyle.Single;
            dataGridView1.ColumnHeadersDefaultCellStyle.BackColor = Color.White;
            dataGridView1.ColumnHeadersDefaultCellStyle.ForeColor = Color.Black;
            dataGridView1.ColumnHeadersHeightSizeMode = DataGridViewColumnHeadersHeightSizeMode.DisableResizing;

            for (int i = 0; i < 50; i++)
            {
                DataGridViewColumn dc = new DataGridViewColumn();
                dataGridView1.Columns.Add("ch" + i.ToString(), "C" + i.ToString());
                dataGridView1.Columns[i].Width = 30;
                dataGridView1.Columns[i].SortMode = DataGridViewColumnSortMode.NotSortable;
                dataGridView1.Columns[i].HeaderCell.Style.Alignment = DataGridViewContentAlignment.BottomCenter;
                this.dataGridView1.Columns[i].Resizable = DataGridViewTriState.False;

                Application.DoEvents();
            }

            //dataGridView1.RowHeadersBorderStyle = DataGridViewHeaderBorderStyle.None;
            dataGridView1.SelectionMode = DataGridViewSelectionMode.CellSelect;
            for (int j = 0; j < 100; j++)
            {
                int idx = dataGridView1.Rows.Add();
                dataGridView1.Rows[idx].HeaderCell.Value = "R" + j.ToString();
                dataGridView1.Rows[idx].HeaderCell.Style.WrapMode = DataGridViewTriState.True;
                dataGridView1.Rows[idx].HeaderCell.Style.SelectionBackColor = Color.White;
                dataGridView1.Rows[idx].HeaderCell.Style.BackColor = Color.White;
                dataGridView1.Rows[idx].Resizable = DataGridViewTriState.False;

                Application.DoEvents();

            }

        }

        private void dataGridView1_RowPostPaint(object sender, DataGridViewRowPostPaintEventArgs e)
        {
            if (e.RowIndex == -1) return;

            int rem = -1;
            Math.DivRem(e.RowIndex + 1, 2, out rem);
            if (rem == 0)
            {
                int i = e.RowIndex - 2;
                Rectangle r1 = this.dataGridView1.GetCellDisplayRectangle(-1, i, true);

                r1.X += 1;
                r1.Y += 1;

                r1.Width = r1.Width;
                r1.Height = r1.Height * 2;

                e.Graphics.FillRectangle(new SolidBrush(Color.LightYellow), r1);

                StringFormat format = new StringFormat()
                {
                    Alignment = StringAlignment.Center,
                    LineAlignment = StringAlignment.Center
                };
                e.Graphics.DrawString(i.ToString(),
                    this.dataGridView1.ColumnHeadersDefaultCellStyle.Font,
                    new SolidBrush(this.dataGridView1.RowHeadersDefaultCellStyle.ForeColor),
                    r1,
                    format);

                Pen p = new Pen(Color.Red);

                Point pTopLeft = new Point(r1.X - 1, r1.Y - 2);
                Point pTopRight = new Point(r1.X + r1.Width - 2, r1.Y - 2);
                e.Graphics.DrawLine(p, pTopLeft, pTopRight);

                Point pBotRight = new Point(r1.X + r1.Width - 2, r1.Y + r1.Height);
                e.Graphics.DrawLine(p, pTopRight, pBotRight);

            }
        }
    }
}

Answer 1

this.dataGridView1.RowValidating += (s, e) => this.dataGridView1.Invalidate();

添加它，现在可以了。