MD5加密（文件和字符串，支持拖拽）

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;
using System.Security.Cryptography;
using System.IO;
using System.Threading;

namespace MD5
{
    public partial class Form1 : Form
    {
        public Form1()
        {
            InitializeComponent();
        }
        string path = "";
        private void button1_Click(object sender, EventArgs e)
        {
           
            if(this.openFileDialog1.ShowDialog()!=DialogResult.Cancel)
            {
                path=this.openFileDialog1.FileName;
            }
            if(!File.Exists(path)||path.Length==0)
            {
               
                return;
            }
            this.textBox3.Text = path;
            start();
            
        }
        Thread thrad = null;
        public void start()
        {
            this.label3.Visible = true;
            this.textBox1.Clear();
            thrad = new Thread(new ThreadStart(GetMD5));
            thrad.Start();
        }


        public void  GetMD5()
        {
            try
            {
                FileStream fs = new FileStream(path, FileMode.Open, FileAccess.Read, FileShare.Read);
                MD5CryptoServiceProvider getmd5 = new MD5CryptoServiceProvider();
                byte[] hash = getmd5.ComputeHash(fs);
                string result = BitConverter.ToString(hash);
                result = result.Replace("-", "");
                this.label3.Visible = false;
                this.textBox1.Text = result;
            }
            catch (Exception ex)
            {

                ex.ToString();
            }
            finally
            {
                if (thrad.IsAlive)
                {
                    thrad.Abort();
                }
            }
           
        }

        private void button2_Click(object sender, EventArgs e)
        {
            if (thrad != null)
            {
                if (thrad.IsAlive)
                {
                    thrad.Abort();
                }
            }
            Application.Exit();
        }

        private void button4_Click(object sender, EventArgs e)
        {
            this.textBox1.Clear();
            this.textBox2.Clear();
            this.textBox3.Clear();
        }

        private void button3_Click(object sender, EventArgs e)
        {
            if (this.textBox1.Text.Trim().Equals("") || this.textBox2.Text.Trim().Equals(""))
            {
                MessageBox.Show("请填写MD5值");
                return;
            }

            if (this.textBox1.Text.Trim().CompareTo(this.textBox2.Text.Trim()) == 0)
            {
                MessageBox.Show("相同");
            }
            else
            {
                MessageBox.Show("不相同");
            }
        }

        private void Form1_Load(object sender, EventArgs e)
        {
            this.label3.Visible = false;
        }

        private void Form1_DragEnter(object sender, DragEventArgs e)
        {
            if (e.Data.GetDataPresent(DataFormats.FileDrop))
            {
                this.textBox3.Clear();
                e.Effect = DragDropEffects.Link;
            }
            else
            {
                e.Effect = DragDropEffects.None;
            }
        }

        private void Form1_DragDrop(object sender, DragEventArgs e)
        {
            this.textBox3.Text = ((System.Array)e.Data.GetData(DataFormats.FileDrop)).GetValue(0).ToString();
            path = this.textBox3.Text.Trim();
            if (!File.Exists(path) || path.Length == 0)
            {
                MessageBox.Show("文件有误");
                return;
            }
            start();
        }

        private void button5_Click(object sender, EventArgs e)
        {
            if (!File.Exists(path) || path.Length == 0)
            {
                MessageBox.Show("文件有误");
                return;
            }
            start();
            

        }

        private void button6_Click(object sender, EventArgs e)
        {
            string Test = this.textBox2.Text.Trim();
            if (Test.Length == 0)
            {
                return;
            }
            GetString(Test);
        }

        public void GetString(string Test)
        {
            System.Security.Cryptography.MD5 md5 = System.Security.Cryptography.MD5.Create();
            StringBuilder pwd = new StringBuilder();
            byte[] s = md5.ComputeHash(Encoding.UTF8.GetBytes(Test));
          
            for (int i = 0; i < s.Length; i++)
            {
              

               pwd.Append(s[i].ToString("X2"));

            }
            this.textBox1.Text = pwd.ToString();

        }

        private void button7_Click(object sender, EventArgs e)
        {
            string s = string.Format("欢迎你使用MD5加密小软件，\n1:   选择文件就自动计算MD5\n2:   计算按钮基本用不到，是对拖拉的备用\n3:   输入MD5可以像计算出来的比较\n4:   也可以在输入框输入字符串进行加密\n  感谢你的使用_CL！");
               MessageBox.Show(s,"CL");
        }
    }
}