winform选择文件夹

using System;
using System.Windows.Forms;

namespace WindowsFormsApp1
{
    public partial class Form1 : Form
    {
        public Form1()
        {
            InitializeComponent();
        }

        /// <summary>
        /// 好用一点的打开目录
        /// </summary>
        /// <param name="sender"></param>
        /// <param name="e"></param>
        private void button1_Click(object sender, EventArgs e)
        {
            OpenFileDialog ofd = new OpenFileDialog();
            ofd.DefaultExt = "xls";
            ofd.FileName = "默认名字";
            ofd.Filter = "Excel Document(*.xls)|*.xls";
            //如果设置了默认路径，那下次打开依然是这个默认路径，
            //不应该和RestoreDirectory =true同时使用。
            //sfd.InitialDirectory = "C:\";
            //保存路径，每次打开，都选择上次的目录，
            ofd.RestoreDirectory = true; 
            if (ofd.ShowDialog() != System.Windows.Forms.DialogResult.OK)
            {
                return;
            }
        }

        /// <summary>
        /// 难用的打开目录
        /// </summary>
        /// <param name="sender"></param>
        /// <param name="e"></param>
        private void button2_Click(object sender, EventArgs e)
        {
            FolderBrowserDialog fbd = new FolderBrowserDialog();
            //即使设置了这个默认路径，但滚动条不会自动滚动到那儿
            fbd.SelectedPath = "D:\app";
            if(fbd.ShowDialog()!=DialogResult.OK)
            {
                return;
            }
        }
    }
}

第一种：

 第二种：