在DataGrid中添加图片列(C#)

重DataGridTextBoxColumn类

using System;
using System.Windows.Forms;
using System.Drawing;
using System.Data;
using System.Collections;

namespace ImageCellInDataGrid
{
    /**//// <summary>
    /// Summary description for DataGridImageCell.
    /// </summary>
    public class DataGridImageCell : DataGridTextBoxColumn
    {
        private ArrayList theImages1;
        public DataGridImageCell()
        {
            
        }
        public ArrayList theImages
        {
            get{return theImages1;}
            set{theImages1 = value;}
        }

        protected override void Paint(System.Drawing.Graphics g, System.Drawing.Rectangle bounds, System.Windows.Forms.CurrencyManager source, int rowNum, System.Drawing.Brush backBrush, System.Drawing.Brush foreBrush, bool alignToRight)
        {
            object o = this.GetColumnValueAtRow(source, rowNum);
            if(o != null)
            {
                int i = (int)o;
                g.FillRectangle(backBrush, bounds);
                
                Bitmap bmp = (Bitmap)theImages[i];
            
                //GridImageCellDrawOption cellDrawOption = GridImageCellDrawOption.NoResize;
                //GridImageCellDrawOption cellDrawOption = GridImageCellDrawOption.FitProportionally;
                GridImageCellDrawOption cellDrawOption = GridImageCellDrawOption.FitToCell;
                
                
                System.Drawing.GraphicsUnit gu = System.Drawing.GraphicsUnit.Point;
                    
                RectangleF srcRect = bmp.GetBounds(ref gu);
                Rectangle destRect = Rectangle.Empty;

                Region saveRegion = g.Clip;

                switch(cellDrawOption)
                {
                    case GridImageCellDrawOption.FitToCell:
                        destRect = bounds;
                        break;
                    case GridImageCellDrawOption.NoResize:
                        destRect = new Rectangle(bounds.X, bounds.Y, (int) srcRect.Width, (int) srcRect.Height);
                        g.Clip = new Region(bounds);
                        break;
                    case GridImageCellDrawOption.FitProportionally:
                    {
                        float srcRatio =  srcRect.Width / srcRect.Height;
                        float tarRatio = (float) bounds.Width / bounds.Height;
                        destRect = bounds;
                        if( tarRatio < srcRatio )
                        {
                            destRect.Height = (int) (destRect.Width * srcRatio);    
                        }
                        else
                        {
                            destRect.Width = (int) (destRect.Height * srcRatio);
                        }
                    }
                        break;
                        
                    default:
                        break;
                }

                if(!destRect.IsEmpty)
                    g.DrawImage(bmp,  destRect, srcRect, gu);

                g.Clip = saveRegion;
            }
        }

        protected override void Edit(System.Windows.Forms.CurrencyManager source, int rowNum, System.Drawing.Rectangle bounds, bool readOnly, string instantText, bool cellIsVisible)
        {
        //overridden to avoid editing
        }

        public enum GridImageCellDrawOption
        {
            FitToCell      = 0,
            NoResize      = 1,
            FitProportionally = 2,
        };
    }
}

测试代码

private System.Windows.Forms.DataGrid dataGrid1;

private void Form1_Load(object sender, System.EventArgs e)
        {

            //create a datatable
            DataTable dt = new DataTable("MyTable");

            dt.Columns.Add(new DataColumn("Col0"));
            dt.Columns.Add(new DataColumn("Images",typeof(int)));

            Random r = new Random();
            for(int i = 0; i < nRows; ++i)
            {
                DataRow dr = dt.NewRow();
                dr[0] = string.Format("row{0}", i);
                dr[1] = r.Next(4);
                dt.Rows.Add(dr);
            }

            //store bitmaps in an arraylist
            bitMaps = new ArrayList();
            System.IO.Stream strm = GetType().Assembly.GetManifestResourceStream("ImageCellInDataGrid.Blue hills.jpg");
            bitMaps.Add(new Bitmap(strm));
            strm = GetType().Assembly.GetManifestResourceStream("ImageCellInDataGrid.Sunset.jpg");
            bitMaps.Add(new Bitmap(strm));
            strm = GetType().Assembly.GetManifestResourceStream("ImageCellInDataGrid.Water lilies.jpg");
            bitMaps.Add(new Bitmap(strm));
            strm = GetType().Assembly.GetManifestResourceStream("ImageCellInDataGrid.Winter.jpg");
            bitMaps.Add(new Bitmap(strm));
            

            DataGridTableStyle tableStyle = new DataGridTableStyle();
            tableStyle.MappingName = "MyTable";

            DataGridTextBoxColumn tbc = new DataGridTextBoxColumn();
            tbc.MappingName = "Col0";
            tbc.HeaderText = "Column 1";
            tbc.Width = 50;
            tableStyle.GridColumnStyles.Add(tbc);

            int width = this.dataGrid1.ClientSize.Width - tbc.Width - this.dataGrid1.RowHeaderWidth - 4;
            DataGridImageCell tbc1 = new DataGridImageCell();
            tbc1.MappingName = "Images";
            tbc1.HeaderText = "Images";
            tbc1.theImages = bitMaps;
            tbc1.Width = width;
            tableStyle.GridColumnStyles.Add(tbc1);

            this.dataGrid1.TableStyles.Add(tableStyle);
            this.dataGrid1.DataSource = dt;
            dt.DefaultView.AllowNew = false;

            Rectangle rect = this.dataGrid1.GetCellBounds(0,0);
            topPos = rect.Top;
            int height = (this.dataGrid1.ClientSize.Height - topPos - nRows) / nRows;
            tableStyle.PreferredRowHeight = height;
            this.dataGrid1.DataSource = null;
            this.dataGrid1.DataSource = dt;
            
        }