dataGridView 合并表头

form代码：

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 WindowsFormsApplication1
{
    public partial class Form1 : Form
    {
        public Form1()
        {
            InitializeComponent();
            exGridView.isEnLarged = false;
        }

        private void dataGridView1_CellPainting(object sender, DataGridViewCellPaintingEventArgs e)
        {
            exGridView exG = new exGridView();
            List<string> colNameCollection = new List<string>();
            for (int i = 1; i <= 10; i++)
            {
                //"colDraw"+i.ToString()是columnName的属性值
                colNameCollection.Add("Column" + i.ToString());
            }
            exG.MergeHeader(sender, e, colNameCollection, "0-9中奖号码分布图");

        }
    }
}

 

 

类代码：

using System.Collections.Generic;
using System.Drawing;
using System.Windows.Forms;
namespace WindowsFormsApplication1
{
    public class exGridView
    {
        #region 合并列时使用到的位置和大小属性
        int cTop = 0;//被合并表头区域的顶部坐标
        int cLeft = 0;//被合并表头区域的左边坐标
        /// <summary>
        /// 被合并表头区域的宽
        /// </summary>
        int cWidth = 0;
        int cHeight = 0;//。。。高
        #endregion
        /// <summary>
        /// 判断是否已经将datagridview的表头变高了，只增高一次。
        /// </summary>
        public static bool isEnLarged = false;

        /// <summary>
        /// 合并表头,用在dataGridView的CellPainting事件中。
        /// </summary>
        /// <param name="sender">需要重绘的dataGridview</param>
        /// <param name="e">CellPainting中的参数</param>
        ///<param name="colName">列的集合(列必须是连续的，第一列放在最前面)</param>
        /// <param name="headerText">列合并后显示的文本</param>
        public void MergeHeader(object sender, DataGridViewCellPaintingEventArgs e, List<string> colNameCollection, string headerText)
        {
            if (e.RowIndex == -1)
            {
                if (e.ColumnIndex != -1)
                {
                    DataGridView dataGridView1 = sender as DataGridView;

                    string colName = dataGridView1.Columns[e.ColumnIndex].Name;
                    //if (!isEnLarged)
                    //{
                    //    //0.扩展表头高度为当前的2倍
                    //    dataGridView1.ColumnHeadersHeightSizeMode = DataGridViewColumnHeadersHeightSizeMode.EnableResizing;
                    //    dataGridView1.ColumnHeadersHeight = e.CellBounds.Height * 2;
                    //    isEnLarged = true;
                    //}
                    if (colNameCollection.Contains(colName))
                    {
                        #region 重绘列头
                        //1.计算colLen个列的区域
                        if (colNameCollection.IndexOf(colName) == 0)
                        {
                            cTop = e.CellBounds.Top;
                            cLeft = e.CellBounds.Left;

                            cWidth = e.CellBounds.Width;
                            cHeight = e.CellBounds.Height;
                            //cHeight = e.CellBounds.Height / 2;

                            foreach (string colNameItem in colNameCollection)
                            {
                                if (colNameItem.Equals(colName))
                                {//除去自己一个，加了之后colLen-1个列的宽
                                    continue;
                                }
                                cWidth += dataGridView1.Columns[colNameItem].Width;
                            }
                        }

                        Rectangle cArea = new Rectangle(cLeft, cTop, cWidth, cHeight);
                        //2.把区域设置为背景色，没有列的分线及任何文字。
                        using (Brush backColorBrush = new SolidBrush(e.CellStyle.BackColor))
                        {
                            e.Graphics.FillRectangle(backColorBrush, cArea);

                        }
                        ////3.绘制新列头的边框
                        //using (Pen gridPen = new Pen(dataGridView1.GridColor))
                        //{
                        //    //3.1 上部边框
                        //    e.Graphics.DrawLine(gridPen, cLeft, cTop, cLeft + cWidth, cTop);
                        //    using (Pen hilightPen = new Pen(Color.WhiteSmoke))
                        //    {
                        //        //3.2 顶部高光
                        //        e.Graphics.DrawLine(hilightPen, cLeft, cTop + 1, cLeft + cWidth, cTop + 1);
                        //        //3.3 左部反光线
                        //        e.Graphics.DrawLine(hilightPen, cLeft, cTop + 3, cLeft, cTop + cHeight - 2);
                        //    }
                        //    //3.4 下部边框
                        //    e.Graphics.DrawLine(gridPen, cLeft, cTop + cHeight - 1, cLeft + cWidth, cTop + cHeight - 1);
                        //    //3.5 右部边框                        
                        //    e.Graphics.DrawLine(gridPen, cLeft + cWidth - 1, cTop, cLeft + cWidth - 1, cTop + cHeight);//(cTop+cHeight)/2);
                        //}
                        ////4.写文本
                        //if (colNameCollection.IndexOf(colName) == 0)
                        //{//不是第一列则不写文字。
                        //    int wHeadStr = (int)(headerText.Length * e.CellStyle.Font.SizeInPoints);
                        //    int wHeadCell = cWidth;
                        //    int pHeadLeft = (wHeadCell - wHeadStr) / 2 - 6;
                        //    using (Brush foreBrush = new SolidBrush(e.CellStyle.ForeColor))
                        //    {
                        //        e.Graphics.DrawString(headerText, e.CellStyle.Font, foreBrush, new PointF(cLeft + pHeadLeft, cTop + 3));
                        //    }
                        //}

                        ////5 绘制子列背景
                        //int FatherColHeight = e.CellBounds.Height / 2;//上面一行的高度 
                        //using (Brush backColorBrush = new SolidBrush(e.CellStyle.BackColor))
                        //{
                        //    e.Graphics.FillRectangle(backColorBrush, new Rectangle(e.CellBounds.X, e.CellBounds.Y + FatherColHeight, e.CellBounds.Width - 1, e.CellBounds.Height / 2 - 1));
                        //}
                        ////5.1绘制子列的边框                   
                        //using (Pen gridPen = new Pen(dataGridView1.GridColor))
                        //{
                        //    using (Pen hilightPen = new Pen(Color.WhiteSmoke))
                        //    {
                        //        //5.2 左部反光线
                        //        e.Graphics.DrawLine(hilightPen, cLeft, cTop + 3 + FatherColHeight, cLeft, cTop + cHeight - 2 + FatherColHeight);
                        //    }
                        //    //5.3 下部边框
                        //    e.Graphics.DrawLine(gridPen, cLeft, cTop + cHeight - 1 + FatherColHeight, cLeft + cWidth, cTop + cHeight - 1 + FatherColHeight);

                        //    //5.4 右部边框 
                        //    e.Graphics.DrawLine(gridPen, e.CellBounds.X + e.CellBounds.Width - 1, e.CellBounds.Top + FatherColHeight, e.CellBounds.X + e.CellBounds.Width - 1, e.CellBounds.Top + e.CellBounds.Height + FatherColHeight);//(cTop+cHeight)/2);                    

                        //}
                        ////5.5 写子列的文本
                        //int wStr = (int)(dataGridView1.Columns[e.ColumnIndex].HeaderText.Length * e.CellStyle.Font.SizeInPoints);
                        //int wCell = e.CellBounds.Width;
                        //int pLeft = (wCell - wStr) / 2;//相对CELL左边框的左坐标

                        //using (Brush foreBrush = new SolidBrush(e.CellStyle.ForeColor))
                        //{
                        //    e.Graphics.DrawString(dataGridView1.Columns[e.ColumnIndex].HeaderText, e.CellStyle.Font, foreBrush, new PointF(e.CellBounds.X + pLeft, cTop + 3 + FatherColHeight));
                        //}
                        #endregion
                        e.Handled = true;
                    }
                }
            }
        }
    }
}