OpenFileDialog

using System;
using System.Collections.Generic;
using System.ComponentModel;
using System.Data;
using System.Drawing;
using System.IO;
using System.Linq;
using System.Text;
using System.Threading.Tasks;
using System.Windows.Forms;

namespace WindowsFormsApp4
{
public partial class Form1 : Form
{
public Form1()
{
InitializeComponent();
}

    private void button1_Click(object sender, EventArgs e)//读取文本    {        this.openFileDialog1.Filter = "*.txt|*.txt";        if (openFileDialog1.ShowDialog() == System.Windows.Forms.DialogResult.OK)        {            StreamReader sr = new StreamReader(openFileDialog1.FileName);            MessageBox.Show(sr.ReadToEnd());            sr.Close();        }    }    private void button2_Click(object sender, EventArgs e)//选择图片    {        this.openFileDialog1.Filter = "(*.jpg;*.jpg;*.jpeg;*.gif;*.png)|*.jpg;*.jpeg;*.gif;*.png";        if (openFileDialog1.ShowDialog() == DialogResult.OK)        {            MessageBox.Show("" + openFileDialog1.FileName);            pictureBox1.ImageLocation = openFileDialog1.FileName;        }    }    //拷贝到制定文件夹    private void button4_Click(object sender, EventArgs e)    {        string oldpath = pictureBox1.ImageLocation;        string fileName = System.IO.Path.GetFileName(oldpath).ToString();        string copypath = System.IO.Directory.GetCurrentDirectory() + "/images/";//当前运行程序的images文件夹        if (!Directory.Exists(copypath))//如果这个目录不存在就创建        {            Directory.CreateDirectory(copypath);        }        File.Copy(pictureBox1.ImageLocation, copypath + fileName, true);        MessageBox.Show("保存成功");    }    //另存    private void button3_Click(object sender, EventArgs e)    {        SaveFileDialog saveFileDialog1 = new SaveFileDialog();        string oldpath = pictureBox1.ImageLocation;        string fileName = System.IO.Path.GetFileName(oldpath).ToString();        string houzui = System.IO.Path.GetExtension(oldpath).ToString();        saveFileDialog1.Filter = "txt files (*.txt)|*.txt|All files (*.*)|*.*";        saveFileDialog1.FilterIndex = 2;        saveFileDialog1.RestoreDirectory = true;        if (saveFileDialog1.ShowDialog() == DialogResult.OK)        {                MessageBox.Show(saveFileDialog1.FileName);                File.Copy(pictureBox1.ImageLocation, saveFileDialog1.FileName+houzui, true);        }    }}

}