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;
}

}

}
}

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