comboBox with images

Myth丶恋晨 2022-08-26 05:58 285阅读 0赞

先看效果图：

![Center][]

实现步骤如下：

添加MyItem类：

using System;
    using System.Collections.Generic;
    using System.Linq;
    using System.Text;
    using System.Drawing;//
    
    namespace rePaint
    {
        class MyItem
        {
            //项文本内容
            private String Text;
    
            //项图片
            public Image Img;
    
            //构造函数
            public MyItem(String text, Image img)
            {
                Text = text;
                Img = img;
            }
    
            //重写ToString函数，返回项文本
            public override string ToString()
            {
                return Text;
            }
        }
    }

在主程序中：

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;
    using System.Drawing.Drawing2D; 
    
    namespace rePaint
    {
        public partial class Form1 : Form
        {
            private int itemHeight=30;
            public Form1()
            {
                InitializeComponent();
            }
    
            private void Form1_Load(object sender, EventArgs e)
            {
                //添加项
                comboBox1.Items.Add(new MyItem("000000", Image.FromFile(Application.StartupPath + @"\0.gif")));
                comboBox1.Items.Add(new MyItem("111111", Image.FromFile(Application.StartupPath + @"\1.gif")));
                comboBox1.Items.Add(new MyItem("222222", Image.FromFile(Application.StartupPath + @"\2.gif")));
                comboBox1.Items.Add(new MyItem("333333", Image.FromFile(Application.StartupPath + @"\3.gif")));
    
                //默认选中项索引
                comboBox1.SelectedIndex = 0;//不能删除
    
                //自绘组合框需要设置的一些属性
                comboBox1.DrawMode = DrawMode.OwnerDrawFixed;//不能设置为：DrawMode.OwnerDrawVariable
                comboBox1.DropDownStyle = ComboBoxStyle.DropDownList;
    
                comboBox1.ItemHeight = itemHeight;
    
                //添加DrawItem事件处理函数
                comboBox1.DrawItem += ComboBox1_DrawItem;
            }
    
            private void ComboBox1_DrawItem(object sender, DrawItemEventArgs e)
            {
                //鼠标选中在这个项上
                if ((e.State & DrawItemState.Selected) != 0)
                {
                    //渐变画刷
                    LinearGradientBrush brush = new LinearGradientBrush(e.Bounds, Color.FromArgb(255, 251, 237),
                                                     Color.FromArgb(255, 236, 181), LinearGradientMode.Vertical);
                    //填充区域
                    Rectangle borderRect = new Rectangle(3, e.Bounds.Y, e.Bounds.Width - 4, e.Bounds.Height - 2);
    
                    e.Graphics.FillRectangle(brush, borderRect);
    
                    //画边框
                    Pen pen = new Pen(Color.FromArgb(229, 195, 101));
                    e.Graphics.DrawRectangle(pen, borderRect);
                }
                else
                {
                    SolidBrush brush = new SolidBrush(Color.FromArgb(255, 255, 255));
                    e.Graphics.FillRectangle(brush, e.Bounds);
                }
    
                //获得项图片,绘制图片
                MyItem item = (MyItem)comboBox1.Items[e.Index];
                Image img = item.Img;
    
                //图片绘制的区域
                Rectangle imgRect = new Rectangle(2, e.Bounds.Y + 1, itemHeight - 2, itemHeight - 2);//(x,y,width,height)
                e.Graphics.DrawImage(img, imgRect);
    
                //文本内容显示区域
                Rectangle textRect =
                    new Rectangle(imgRect.Right + 2, imgRect.Y, e.Bounds.Width - imgRect.Width, e.Bounds.Height - 2);
    
                //获得项文本内容,绘制文本
                String itemText = comboBox1.Items[e.Index].ToString();
    
                //文本格式垂直居中
                StringFormat strFormat = new StringFormat();
                strFormat.LineAlignment = StringAlignment.Center;
                e.Graphics.DrawString(itemText, new Font("宋体", 12), Brushes.Black, textRect, strFormat);
            } 
        }
    }

[Center]: /images/20220824/98261545dad74261ad168520110fdafa.png