为ComboBox控件添加图片

扩展类 ComboBoxEx.cs

using System;
using System.Windows.Forms;
using System.Windows.Forms.Design;
using System.Drawing;

namespace Mengxianhui.ComboBoxEx
{
    class ComboBoxEx : ComboBox
    {
        private ImageList imageList;
        public ImageList ImageList
        {
            get { return imageList; }
            set { imageList = value; }
        }

        public ComboBoxEx()
        {
            DrawMode = DrawMode.OwnerDrawFixed;
        }

        protected override void OnDrawItem(DrawItemEventArgs ea)
        {
            ea.DrawBackground();
            ea.DrawFocusRectangle();

            ComboBoxExItem item;
            Size imageSize = imageList.ImageSize;
            Rectangle bounds = ea.Bounds;

            try
            {
                item = (ComboBoxExItem)Items[ea.Index];

                if (item.ImageIndex != -1)
                {
                    imageList.Draw(ea.Graphics, bounds.Left, bounds.Top, item.ImageIndex);
                    ea.Graphics.DrawString(item.Text, ea.Font, new SolidBrush(ea.ForeColor), bounds.Left + imageSize.Width, bounds.Top);
                }
                else
                {
                    ea.Graphics.DrawString(item.Text, ea.Font, new SolidBrush(ea.ForeColor), bounds.Left, bounds.Top);
                }
            }
            catch
            {
                if (ea.Index != -1)
                {
                    ea.Graphics.DrawString(Items[ea.Index].ToString(), ea.Font, new SolidBrush(ea.ForeColor), bounds.Left, bounds.Top);
                }
                else
                {
                    ea.Graphics.DrawString(Text, ea.Font, new SolidBrush(ea.ForeColor), bounds.Left, bounds.Top);
                }
            }

            base.OnDrawItem(ea);
        }
    }

    class ComboBoxExItem
    {
        private string _text;
        public string Text
        {
            get { return _text; }
            set { _text = value; }
        }

        private int _imageIndex;
        public int ImageIndex
        {
            get { return _imageIndex; }
            set { _imageIndex = value; }
        }

        public ComboBoxExItem() : this("")
        {
        }

        public ComboBoxExItem(string text) : this(text, -1)
        {
        }

        public ComboBoxExItem(string text, int imageIndex)
        {
            _text = text;
            _imageIndex = imageIndex;
        }

        public override string ToString()
        {
            return _text;
        }
    }
}

使用方法：

1.在form类里声明

public class Form1 : System.Windows.Forms.Form
{
    private System.ComponentModel.IContainer components;
    private  ComboBoxEx comboBox2;

2.初始化组件

private void InitializeComponent()
{
    ComboBoxEx comboBox2 = new ComboBoxEx();
    comboBox2.Width = 200;

    comboBox2.Items.Add(new ComboBoxExItem("【孟宪会之精彩世界】", 0));
    comboBox2.Items.Add(new ComboBoxExItem("【孟宪会之精彩世界】", 1));
    comboBox2.Items.Add(new ComboBoxExItem("【孟宪会之精彩世界】", 2));
    this.Controls.AddRange(new System.Windows.Forms.Control[] {comboBox2});

    ImageList imageList1 = new ImageList();
    imageList1.Images.Add(Image.FromFile(@"D:\TEST\lib\db0.bmp"));
    imageList1.Images.Add(Image.FromFile(@"D:\TEST\lib\db0.bmp"));
    imageList1.Images.Add(Image.FromFile(@"D:\TEST\lib\db0.bmp"));

    comboBox2.ImageList = imageList1;

    this.SuspendLayout();