Winform OpenFileDialog控件, 选择文件控件用法

窗体拖拽一个button，代码样例中使用OpenFileDialog对象new一个新实例，等同于在窗体拖拽OpenFileDialog控件，两种方式都可以，实现功能效果是相同的

using System;
using System.Windows.Forms;

namespace WindowsFormsApp11
{
    public partial class Form1 : Form
    {
        public Form1()
        {
            InitializeComponent();
        }

        private void button1_Click(object sender, EventArgs e)
        {
            string path = "";
            OpenFileDialog openFileDialog1 = new OpenFileDialog();
            // 打开目录定位到当前应用程序目录
            openFileDialog1.InitialDirectory = Application.StartupPath;
            // 设置OpenFileDialog组件的Filter过滤出多种扩展名的文件
            openFileDialog1.Filter = "All files (*.*)|*.*|text files (*.txt;)|*.txt;";
            //openFileDialog1.Filter = "Image Files(*.BMP;*.JPG;*.GIF)|*.BMP;*.JPG;*.GIF|All files(*.*)|*.*";
            // 设置默认文件类型显示顺序
            openFileDialog1.FilterIndex = 2;
            // 是否记忆上次打开的目录  
            openFileDialog1.RestoreDirectory = true;
            if (openFileDialog1.ShowDialog() == DialogResult.OK)
            {
                // 获取文件路径
                path = openFileDialog1.FileName;
                MessageBox.Show(path);
                // 业务操作...
                // 业务操作...
                // 业务操作...
            }
        }
    }
}