c#中实现文件拖放打开的方法

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;

namespace DragDrop
{
    public partial class DragDrop : Form
    {
        public string FilePath;

        public DragDrop()
        {
            InitializeComponent();
        }

        /// <summary>
        /// 获取ListBox的值。
        /// </summary>
        /// <returns></returns>
        public string GetListBoxItem()
        {
            string filePath = string.Empty;

            bool isSelected = IsListBoxSelected();

            if (isSelected==true)
            {
                string listBoxItemValue = lbFilePath.SelectedItem.ToString();

                filePath = listBoxItemValue;
            }
            else
            {
                MessageBox.Show("ListBox must be selected.");
            }

            return filePath;
        }

        /// <summary>
        /// ListBox内的值是否被选中。
        /// </summary>
        /// <returns></returns>
        public bool IsListBoxSelected()
        {
            bool selected;

            if (lbFilePath.SelectedIndex == -1)//SelectedIndex==-1时，表示未选中任何项。
            {
                selected = false;
            }
            else
            {
                selected = true;
            }

            return selected;
        }

        private void lbFilePath_DragEnter(object sender, DragEventArgs e)
        {
            if (e.Data.GetDataPresent(DataFormats.FileDrop))
            {
                e.Effect = DragDropEffects.All;
            }
            else
            {
                e.Effect = DragDropEffects.None;
            }
        }

        private void lbFilePath_DragDrop(object sender, DragEventArgs e)
        {
            string[] s=(string[])e.Data.GetData(DataFormats.FileDrop,false);

            for (int i = 0; i < s.Length; i++)
            {
                lbFilePath.Items.Add(s[i]);
            }
        }

        private void btnOpenFile_Click(object sender, EventArgs e)
        {
            string filePath=GetListBoxItem();

            if (!string.IsNullOrEmpty(filePath))
            {
                System.Diagnostics.Process.Start(filePath);
            }
        }
    }
}

private void Form1_DragEnter(object sender, System.Windows.Forms.DragEventArgs e) 
　　{ 
　　if (e.Data.GetDataPresent(DataFormats.FileDrop)) 
　　e.Effect = DragDropEffects.Link;  
　　else e.Effect = DragDropEffects.None;  
　　} 

　　private void Form1_DragDrop(object sender, System.Windows.Forms.DragEventArgs e) 
　　{ 
　　//其中label1.Text显示的就是拖进文件的文件名； 
　　label1.Text = ((System.Array)e.Data.GetData(DataFormats.FileDrop)).GetValue(0).ToString();  
　　}