如何让组合框的宽度自动适应

在Windows Forms应用程序开发过程中，我们经常会用到组合框（ComboBox），但它的那个下拉列表宽度是固定的，那么如何让它支持自动适应的宽度呢。下面是一个小例子

using System;

using System.Drawing;

using System.Linq;

using System.Windows.Forms;

using System.IO;



namespace WindowsFormsApplication1

{

    public partial class Form1 : Form

    {

        public Form1()

        {

            InitializeComponent();



            Load += new EventHandler(Form1_Load);

        }



        void Form1_Load(object sender, EventArgs e)

        {



            var dir = new DirectoryInfo("e:\\temp");

            var query = from f in dir.GetFiles()

                        select new

                        {

                            FullName = f.FullName,

                            Name = f.Name

                        };



            comboBox1.DataSource = query.ToArray();

            comboBox1.DisplayMember = "Name";

            comboBox1.ValueMember = "FullName";





            

            using (Graphics g = comboBox1.CreateGraphics())

            {

                int widestWidth = comboBox1.DropDownWidth;

                foreach (var item in query.Select(v=>v.Name))

                {

                    int current = (int)g.MeasureString(item, comboBox1.Font).Width;

                    if (current > widestWidth) widestWidth = current;

                }

                comboBox1.DropDownWidth = widestWidth;

            }



        }



    }

}