文件流

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 文件流
{
    public partial class Form1 : Form
    {
        public Form1()
        {
            InitializeComponent();
        }

        private void btnOpen1_Click(object sender, EventArgs e)
        {
            OpenFileDialog readOFD = new OpenFileDialog();
            if (readOFD.ShowDialog() == DialogResult.OK)
            {
                txtPath1.Text = readOFD.FileName;
            }
        }

        private void btnRead_Click(object sender, EventArgs e)
        {
            using (FileStream fs = new FileStream(txtPath1.Text, FileMode.Open))
            {
                byte[] bytearry=new byte[1024*1024*4];
               int length= fs.Read(bytearry,0,bytearry.Length);
               if (length > 0)
               {
                   txtinputbox1.Text = Encoding.UTF8.GetString(bytearry);
               }
            }
           

        }

        private void btnOpen2_Click(object sender, EventArgs e)
        {
            OpenFileDialog writOpneFileDialog = new OpenFileDialog();
            if (writOpneFileDialog.ShowDialog() == DialogResult.OK)
            {
                txtPath2.Text = writOpneFileDialog.FileName;
            }
        }

        private void btnWrite_Click(object sender, EventArgs e)
        {
            using (FileStream fs = new FileStream(txtPath2.Text, FileMode.Create))
            {
                byte[] bytefile=Encoding.UTF8.GetBytes(textBox3.Text.Trim());
                fs.Write(bytefile,0,bytefile.Length);
            }
        }
    }
}