c#—非對(duì)稱加密：加密文件
★★★★★★ ☆☆☆ ★★★★★★
●●○○ 　   聶永  　　　○○●●
§§§§[email protected]§§§§
◆◆□□[email protected]□□◆◆
№№№№№№ ※※※ №№№№№№　　　
說明：
1.你要注意的是讀取文件的兩種不同方式；
2.從已經(jīng)保存的鑰匙文件中讀取其內(nèi)容；
3.這個(gè)程序做的很粗糙（要準(zhǔn)備考外語六級(jí)，要準(zhǔn)備期末考試，實(shí)在很忙啊！），希望諸位能夠完善，然后也發(fā)表出來，在下表示感謝；
4.參考書目： 《c#數(shù)據(jù)安全手冊(cè)》;
5.有做這方面程序的朋友，愿意相交。
代碼部分：

using system;
using system.drawing;
using system.collections;
using system.componentmodel;
using system.windows.forms;
using system.data;
using system.io;
using system.text;
using system.security.cryptography;
using system.threading;

namespace 非對(duì)稱加密
{
 /// <summary>
 /// form1 的摘要說明。
 /// </summary>
 public class form1 : system.windows.forms.form
 {
  private system.windows.forms.tabcontrol tabcontrol1;
  private system.windows.forms.tabpage tabpage1;
  private system.windows.forms.tabpage tabpage2;
  private system.windows.forms.tabpage tabpage3;
  private system.windows.forms.button button1;
  private system.windows.forms.button button2;
  private system.windows.forms.button button3;
  private system.windows.forms.savefiledialog save;
  private system.windows.forms.label label1;
  private system.windows.forms.textbox textbox1;
  private system.windows.forms.button button4;
  private system.windows.forms.button button5;
  private system.windows.forms.label label2;
  private system.windows.forms.richtextbox richtext2;
  private system.windows.forms.openfiledialog open;
  private system.windows.forms.label label3;
  private system.windows.forms.richtextbox richtext3;
  private system.windows.forms.richtextbox richtext;
  private system.windows.forms.button button6;
  private system.windows.forms.button button7;
  private system.windows.forms.button button8;
  private system.windows.forms.textbox textbox2;
  private system.windows.forms.label label4;
  private system.windows.forms.button button9;
  private system.windows.forms.textbox textbox3;
  private system.windows.forms.label label5;
  private system.windows.forms.button button10;
  private system.windows.forms.label label6;
  private system.windows.forms.button button11;
  private system.windows.forms.button button12;
  private system.windows.forms.richtextbox richtext4;
  private system.windows.forms.button button13;
  private system.windows.forms.button button14;
  private system.windows.forms.button button15;
  private system.windows.forms.tabpage tabpage4;
  private system.windows.forms.textbox textbox4;
  private system.windows.forms.button button16;
  private system.windows.forms.textbox textbox5;
  private system.windows.forms.button button17;
  private system.windows.forms.button button18;
  private system.windows.forms.button button19;
  private system.windows.forms.button button20;
  private system.windows.forms.button button21;
  private system.windows.forms.richtextbox richtext5;
  /// <summary>
  /// 必需的設(shè)計(jì)器變量。
  private static rsacryptoserviceprovider crypt;
  private static string  privatekey;
  private static string  publickey;
  private static byte [] bytes;
  private static string  publicinfo;
  private static string  privateinfo;
  private static string  readpublickey;
  private static string  readprivatekey;
  //文件打開和是否讀取鑰匙的標(biāo)記
  private bool openla = false;
  private bool savela = false;
  private bool readpubkey=false;
  private bool readprikey=false;
  private thread th; 
  /// </summary>
  private system.componentmodel.container components = null;

  public form1()
  {
   //
   // windows 窗體設(shè)計(jì)器支持所必需的
   //
   initializecomponent();

   //
   // todo: 在 initializecomponent 調(diào)用后添加任何構(gòu)造函數(shù)代碼
   //
  }
  /// <summary>
  /// 清理所有正在使用的資源。
  /// </summary>
  protected override void dispose( bool disposing )
  {
   if( disposing )
   {
    if (components != null)
    {
     components.dispose();
    }
   }
   base.dispose( disposing );
  }

  #region windows 窗體設(shè)計(jì)器生成的代碼
  /// <summary>
  /// 設(shè)計(jì)器支持所需的方法 - 不要使用代碼編輯器修改
  /// 此方法的內(nèi)容。
  /// </summary>
  private void initializecomponent()
  {
   this.tabcontrol1 = new system.windows.forms.tabcontrol();
   this.tabpage1 = new system.windows.forms.tabpage();
   this.button6 = new system.windows.forms.button();
   this.button3 = new system.windows.forms.button();
   this.button2 = new system.windows.forms.button();
   this.richtext = new system.windows.forms.richtextbox();
   this.button1 = new system.windows.forms.button();
   this.tabpage2 = new system.windows.forms.tabpage();
   this.button8 = new system.windows.forms.button();
   this.button7 = new system.windows.forms.button();
   this.label3 = new system.windows.forms.label();
   this.richtext3 = new system.windows.forms.richtextbox();
   this.label2 = new system.windows.forms.label();
   this.richtext2 = new system.windows.forms.richtextbox();
   this.button5 = new system.windows.forms.button();
   this.button4 = new system.windows.forms.button();
   this.textbox1 = new system.windows.forms.textbox();
   this.label1 = new system.windows.forms.label();
   this.tabpage3 = new system.windows.forms.tabpage();
   this.button15 = new system.windows.forms.button();
   this.button14 = new system.windows.forms.button();
   this.button13 = new system.windows.forms.button();
   this.button12 = new system.windows.forms.button();
   this.button11 = new system.windows.forms.button();
   this.richtext4 = new system.windows.forms.richtextbox();
   this.label6 = new system.windows.forms.label();
   this.button10 = new system.windows.forms.button();
   this.label5 = new system.windows.forms.label();
   this.textbox3 = new system.windows.forms.textbox();
   this.button9 = new system.windows.forms.button();
   this.label4 = new system.windows.forms.label();
   this.textbox2 = new system.windows.forms.textbox();
   this.tabpage4 = new system.windows.forms.tabpage();
   this.save = new system.windows.forms.savefiledialog();
   this.open = new system.windows.forms.openfiledialog();
   this.textbox4 = new system.windows.forms.textbox();
   this.button16 = new system.windows.forms.button();
   this.textbox5 = new system.windows.forms.textbox();
   this.button17 = new system.windows.forms.button();
   this.button18 = new system.windows.forms.button();
   this.button19 = new system.windows.forms.button();
   this.button20 = new system.windows.forms.button();
   this.button21 = new system.windows.forms.button();
   this.richtext5 = new system.windows.forms.richtextbox();
   this.tabcontrol1.suspendlayout();
   this.tabpage1.suspendlayout();
   this.tabpage2.suspendlayout();
   this.tabpage3.suspendlayout();
   this.tabpage4.suspendlayout();
   this.suspendlayout();
   //
   // tabcontrol1
   //
   this.tabcontrol1.controls.add(this.tabpage1);
   this.tabcontrol1.controls.add(this.tabpage2);
   this.tabcontrol1.controls.add(this.tabpage3);
   this.tabcontrol1.controls.add(this.tabpage4);
   this.tabcontrol1.location = new system.drawing.point(8, 64);
   this.tabcontrol1.name = "tabcontrol1";
   this.tabcontrol1.selectedindex = 0;
   this.tabcontrol1.size = new system.drawing.size(568, 368);
   this.tabcontrol1.tabindex = 0;
   //
   // tabpage1
   //
   this.tabpage1.controls.add(this.button6);
   this.tabpage1.controls.add(this.button3);
   this.tabpage1.controls.add(this.button2);
   this.tabpage1.controls.add(this.richtext);
   this.tabpage1.controls.add(this.button1);
   this.tabpage1.location = new system.drawing.point(4, 21);
   this.tabpage1.name = "tabpage1";
   this.tabpage1.size = new system.drawing.size(560, 343);
   this.tabpage1.tabindex = 0;
   this.tabpage1.text = "得到鑰匙";
   //
   // button6
   //
   this.button6.location = new system.drawing.point(216, 288);
   this.button6.name = "button6";
   this.button6.tabindex = 4;
   this.button6.text = "寫入文件";
   this.button6.click += new system.eventhandler(this.button6_click);
   //
   // button3
   //
   this.button3.location = new system.drawing.point(456, 16);
   this.button3.name = "button3";
   this.button3.tabindex = 3;
   this.button3.text = "保存私匙";
   this.button3.click += new system.eventhandler(this.button3_click);
   //
   // button2
   //
   this.button2.location = new system.drawing.point(320, 16);
   this.button2.name = "button2";
   this.button2.tabindex = 2;
   this.button2.text = "保存公鑰";
   this.button2.click += new system.eventhandler(this.button2_click);
   //
   // richtext
   //
   this.richtext.location = new system.drawing.point(16, 56);
   this.richtext.name = "richtext";
   this.richtext.size = new system.drawing.size(520, 184);
   this.richtext.tabindex = 1;
   this.richtext.text = "richtextbox1";
   //
   // button1
   //
   this.button1.location = new system.drawing.point(136, 16);
   this.button1.name = "button1";
   this.button1.size = new system.drawing.size(88, 23);
   this.button1.tabindex = 0;
   this.button1.text = "得到鑰匙信息";
   this.button1.click += new system.eventhandler(this.button1_click);
   //
   // tabpage2
   //
   this.tabpage2.controls.add(this.button8);
   this.tabpage2.controls.add(this.button7);
   this.tabpage2.controls.add(this.label3);
   this.tabpage2.controls.add(this.richtext3);
   this.tabpage2.controls.add(this.label2);
   this.tabpage2.controls.add(this.richtext2);
   this.tabpage2.controls.add(this.button5);
   this.tabpage2.controls.add(this.button4);
   this.tabpage2.controls.add(this.textbox1);
   this.tabpage2.controls.add(this.label1);
   this.tabpage2.location = new system.drawing.point(4, 21);
   this.tabpage2.name = "tabpage2";
   this.tabpage2.size = new system.drawing.size(560, 343);
   this.tabpage2.tabindex = 1;
   this.tabpage2.text = "加密解密文字";
   //
   // button8
   //
   this.button8.location = new system.drawing.point(368, 72);
   this.button8.name = "button8";
   this.button8.tabindex = 9;
   this.button8.text = "讀取私匙";
   this.button8.click += new system.eventhandler(this.button8_click);
   //
   // button7
   //
   this.button7.location = new system.drawing.point(120, 72);
   this.button7.name = "button7";
   this.button7.tabindex = 8;
   this.button7.text = "讀取公匙";
   this.button7.click += new system.eventhandler(this.button7_click);
   //
   // label3
   //
   this.label3.location = new system.drawing.point(304, 128);
   this.label3.name = "label3";
   this.label3.size = new system.drawing.size(100, 16);
   this.label3.tabindex = 7;
   this.label3.text = "解密結(jié)果";
   //
   // richtext3
   //
   this.richtext3.location = new system.drawing.point(280, 152);
   this.richtext3.name = "richtext3";
   this.richtext3.size = new system.drawing.size(272, 160);
   this.richtext3.tabindex = 6;
   this.richtext3.text = "richtextbox2";
   //
   // label2
   //
   this.label2.location = new system.drawing.point(48, 128);
   this.label2.name = "label2";
   this.label2.size = new system.drawing.size(128, 16);
   this.label2.tabindex = 5;
   this.label2.text = "加密窗口：";
   //
   // richtext2
   //
   this.richtext2.location = new system.drawing.point(8, 152);
   this.richtext2.name = "richtext2";
   this.richtext2.size = new system.drawing.size(256, 160);
   this.richtext2.tabindex = 4;
   this.richtext2.text = "richtextbox2";
   //
   // button5
   //
   this.button5.location = new system.drawing.point(352, 96);
   this.button5.name = "button5";
   this.button5.size = new system.drawing.size(112, 23);
   this.button5.tabindex = 3;
   this.button5.text = "使用私匙解密";
   this.button5.click += new system.eventhandler(this.button5_click);
   //
   // button4
   //
   this.button4.location = new system.drawing.point(112, 96);
   this.button4.name = "button4";
   this.button4.size = new system.drawing.size(96, 23);
   this.button4.tabindex = 2;
   this.button4.text = "使用公匙加密";
   this.button4.click += new system.eventhandler(this.button4_click);
   //
   // textbox1
   //
   this.textbox1.location = new system.drawing.point(104, 32);
   this.textbox1.multiline = true;
   this.textbox1.name = "textbox1";
   this.textbox1.size = new system.drawing.size(264, 32);
   this.textbox1.tabindex = 1;
   this.textbox1.text = "textbox1";
   //
   // label1
   //
   this.label1.location = new system.drawing.point(128, 8);
   this.label1.name = "label1";
   this.label1.size = new system.drawing.size(120, 16);
   this.label1.tabindex = 0;
   this.label1.text = "請(qǐng)輸入加密的文字";
   //
   // tabpage3
   //
   this.tabpage3.controls.add(this.button15);
   this.tabpage3.controls.add(this.button14);
   this.tabpage3.controls.add(this.button13);
   this.tabpage3.controls.add(this.button12);
   this.tabpage3.controls.add(this.button11);
   this.tabpage3.controls.add(this.richtext4);
   this.tabpage3.controls.add(this.label6);
   this.tabpage3.controls.add(this.button10);
   this.tabpage3.controls.add(this.label5);
   this.tabpage3.controls.add(this.textbox3);
   this.tabpage3.controls.add(this.button9);
   this.tabpage3.controls.add(this.label4);
   this.tabpage3.controls.add(this.textbox2);
   this.tabpage3.location = new system.drawing.point(4, 21);
   this.tabpage3.name = "tabpage3";
   this.tabpage3.size = new system.drawing.size(560, 343);
   this.tabpage3.tabindex = 2;
   this.tabpage3.text = "加密解密文件";
   //
   // button15
   //
   this.button15.location = new system.drawing.point(208, 128);
   this.button15.name = "button15";
   this.button15.tabindex = 12;
   this.button15.text = "清空文本";
   this.button15.click += new system.eventhandler(this.button15_click);
   //
   // button14
   //
   this.button14.location = new system.drawing.point(432, 88);
   this.button14.name = "button14";
   this.button14.tabindex = 11;
   this.button14.text = "讀取私匙";
   this.button14.click += new system.eventhandler(this.button14_click);
   //
   // button13
   //
   this.button13.location = new system.drawing.point(432, 32);
   this.button13.name = "button13";
   this.button13.tabindex = 10;
   this.button13.text = "讀取公匙";
   this.button13.click += new system.eventhandler(this.button13_click);
   //
   // button12
   //
   this.button12.location = new system.drawing.point(320, 88);
   this.button12.name = "button12";
   this.button12.tabindex = 9;
   this.button12.text = "開始解密";
   this.button12.click += new system.eventhandler(this.button12_click);
   //
   // button11
   //
   this.button11.location = new system.drawing.point(320, 32);
   this.button11.name = "button11";
   this.button11.tabindex = 8;
   this.button11.text = "開始加密";
   this.button11.click += new system.eventhandler(this.button11_click);
   //
   // richtext4
   //
   this.richtext4.location = new system.drawing.point(8, 152);
   this.richtext4.name = "richtext4";
   this.richtext4.size = new system.drawing.size(496, 168);
   this.richtext4.tabindex = 7;
   this.richtext4.text = "";
   //
   // label6
   //
   this.label6.location = new system.drawing.point(16, 120);
   this.label6.name = "label6";
   this.label6.size = new system.drawing.size(168, 23);
   this.label6.tabindex = 6;
   this.label6.text = "加密與解密窗口：";
   //
   // button10
   //
   this.button10.location = new system.drawing.point(224, 88);
   this.button10.name = "button10";
   this.button10.tabindex = 5;
   this.button10.text = "save ...";
   this.button10.click += new system.eventhandler(this.button10_click);
   //
   // label5
   //
   this.label5.location = new system.drawing.point(16, 64);
   this.label5.name = "label5";
   this.label5.size = new system.drawing.size(216, 16);
   this.label5.tabindex = 4;
   this.label5.text = "請(qǐng)保存加密好或者解密后的文件";
   //
   // textbox3
   //
   this.textbox3.location = new system.drawing.point(16, 88);
   this.textbox3.name = "textbox3";
   this.textbox3.size = new system.drawing.size(184, 21);
   this.textbox3.tabindex = 3;
   this.textbox3.text = "textbox3";
   //
   // button9
   //
   this.button9.location = new system.drawing.point(224, 32);
   this.button9.name = "button9";
   this.button9.tabindex = 2;
   this.button9.text = "open ...";
   this.button9.click += new system.eventhandler(this.button9_click);
   //
   // label4
   //
   this.label4.location = new system.drawing.point(16, 8);
   this.label4.name = "label4";
   this.label4.size = new system.drawing.size(216, 16);
   this.label4.tabindex = 1;
   this.label4.text = "請(qǐng)選擇要加密或者解密的文本文件";
   //
   // textbox2
   //
   this.textbox2.location = new system.drawing.point(16, 32);
   this.textbox2.name = "textbox2";
   this.textbox2.size = new system.drawing.size(184, 21);
   this.textbox2.tabindex = 0;
   this.textbox2.text = "textbox2";
   //
   // tabpage4
   //
   this.tabpage4.controls.add(this.richtext5);
   this.tabpage4.controls.add(this.button21);
   this.tabpage4.controls.add(this.button20);
   this.tabpage4.controls.add(this.button19);
   this.tabpage4.controls.add(this.button18);
   this.tabpage4.controls.add(this.button17);
   this.tabpage4.controls.add(this.textbox5);
   this.tabpage4.controls.add(this.button16);
   this.tabpage4.controls.add(this.textbox4);
   this.tabpage4.location = new system.drawing.point(4, 21);
   this.tabpage4.name = "tabpage4";
   this.tabpage4.size = new system.drawing.size(560, 343);
   this.tabpage4.tabindex = 3;
   this.tabpage4.text = "加密解密其它文件";
   //
   // textbox4
   //
   this.textbox4.location = new system.drawing.point(24, 24);
   this.textbox4.name = "textbox4";
   this.textbox4.size = new system.drawing.size(240, 21);
   this.textbox4.tabindex = 0;
   this.textbox4.text = "textbox4";
   //
   // button16
   //
   this.button16.location = new system.drawing.point(304, 24);
   this.button16.name = "button16";
   this.button16.tabindex = 1;
   this.button16.text = "打開";
   this.button16.click += new system.eventhandler(this.button16_click);
   //
   // textbox5
   //
   this.textbox5.location = new system.drawing.point(24, 56);
   this.textbox5.name = "textbox5";
   this.textbox5.size = new system.drawing.size(240, 21);
   this.textbox5.tabindex = 2;
   this.textbox5.text = "textbox5";
   //
   // button17
   //
   this.button17.location = new system.drawing.point(304, 56);
   this.button17.name = "button17";
   this.button17.tabindex = 3;
   this.button17.text = "保存";
   this.button17.click += new system.eventhandler(this.button17_click);
   //
   // button18
   //
   this.button18.location = new system.drawing.point(48, 88);
   this.button18.name = "button18";
   this.button18.tabindex = 4;
   this.button18.text = "讀取公匙";
   this.button18.click += new system.eventhandler(this.button18_click);
   //
   // button19
   //
   this.button19.location = new system.drawing.point(160, 88);
   this.button19.name = "button19";
   this.button19.tabindex = 5;
   this.button19.text = "讀取私匙";
   this.button19.click += new system.eventhandler(this.button19_click);
   //
   // button20
   //
   this.button20.location = new system.drawing.point(112, 144);
   this.button20.name = "button20";
   this.button20.tabindex = 6;
   this.button20.text = "加密文件";
   this.button20.click += new system.eventhandler(this.button20_click);
   //
   // button21
   //
   this.button21.location = new system.drawing.point(232, 144);
   this.button21.name = "button21";
   this.button21.tabindex = 7;
   this.button21.text = "解密文件";
   this.button21.click += new system.eventhandler(this.button21_click);
   //
   // richtext5
   //
   this.richtext5.location = new system.drawing.point(88, 200);
   this.richtext5.name = "richtext5";
   this.richtext5.size = new system.drawing.size(304, 112);
   this.richtext5.tabindex = 8;
   this.richtext5.text = "";
   //
   // form1
   //
   this.autoscalebasesize = new system.drawing.size(6, 14);
   this.clientsize = new system.drawing.size(584, 453);
   this.controls.add(this.tabcontrol1);
   this.name = "form1";
   this.text = "form1";
   this.tabcontrol1.resumelayout(false);
   this.tabpage1.resumelayout(false);
   this.tabpage2.resumelayout(false);
   this.tabpage3.resumelayout(false);
   this.tabpage4.resumelayout(false);
   this.resumelayout(false);

  }
  #endregion

  /// <summary>
  /// 應(yīng)用程序的主入口點(diǎn)。
  /// </summary>
  [stathread]
  static void main()
  {
   application.run(new form1());
  }
        //得到鑰匙信息  
  private void button1_click(object sender, system.eventargs e)
  {
   crypt=new rsacryptoserviceprovider();
   publickey=crypt.toxmlstring(false);
   richtext.text="導(dǎo)出秘匙的情況下：/n"+publickey+"/n";
   privatekey=crypt.toxmlstring(true);
   string info="僅僅導(dǎo)出公匙的情況下：/n"+privatekey+"/n";
   richtext.appendtext(info);
   crypt.clear(); 
  }
        //保存公匙信息
  private void button2_click(object sender, system.eventargs e)
  {
              
   save=new savefiledialog();
   save.filter="file text (*.txt)|*.txt|all file (*.*)|*.*";
   save.showdialog();
   publicinfo=save.filename;  
  }
        //保存密匙信息
  private void button3_click(object sender, system.eventargs e)
  {
   save=new savefiledialog();
   save.filter="file text (*.txt)|*.txt|all file (*.*)|*.*";
   save.showdialog();
   privateinfo=save.filename;   
  } 
        //用公匙加密
  private void button4_click(object sender, system.eventargs e)
  {
   if(textbox1.text =="")
   {   
    messagebox.show("加密文字信息不能為空！");
    return;   
   }
   if(readpubkey==false)
   {
    messagebox.show("請(qǐng)打開公鑰所在的文件！");
    return;
   }
   try
   {
    crypt=new rsacryptoserviceprovider();
    utf8encoding enc=new utf8encoding();
    bytes=enc.getbytes(textbox1.text);
    crypt.fromxmlstring(  readpublickey );
    bytes = crypt.encrypt( bytes,false );
    string encryttext=enc.getstring(bytes);
    richtext2.text="加密結(jié)果：/n"+encryttext+"/n"+"加密結(jié)束！";
   }
   catch
   {
    messagebox.show("請(qǐng)檢查是否打開公匙或者公匙是否損壞！");
   
   }
  }
        //使用私匙解密
  private void button5_click(object sender, system.eventargs e)
  {
   if(readprikey==false)
   {
    messagebox.show("請(qǐng)打開密匙所在的文件！");
    return;
   }
   try
   {
    utf8encoding enc=new utf8encoding();
    byte [] decryptbyte;
    crypt.fromxmlstring ( readprivatekey ) ;
    decryptbyte = crypt.decrypt( bytes,false );
    string decrypttext=enc.getstring( decryptbyte );
    richtext3.text = "解密結(jié)果：/n" + decrypttext + "/n" + "解密結(jié)束！" ;
   }
   catch
   {
    messagebox.show("請(qǐng)檢查是否打開私匙或者私匙是否損壞！");
   
   }
  }
  //把鑰匙信息寫入文件
  private void button6_click(object sender, system.eventargs e)
  {   
   streamwriter one=new streamwriter(publicinfo,true,utf8encoding.utf8);
   one.write(publickey);
   streamwriter two=new streamwriter(privateinfo,true,utf8encoding.utf8);
   two.write(privatekey);
   one.flush();
   two.flush();
   one.close();
   two.close();
   messagebox.show("成功保存公匙和密匙！"); 
  }
        //從文件中讀取公匙信息
  private void button7_click(object sender, system.eventargs e)
  {   
      readpublickey = readpublickey();
   readpubkey=true;
  }
 
        //從文件中讀取私匙信息
  private void button8_click(object sender, system.eventargs e)
  {
   
      readprivatekey  = readprivatekey();
   readprikey = true;
  }
 
        //打開加密或者解密的文件
  private void button9_click(object sender, system.eventargs e)
  {
      open = new openfiledialog( );
   open.filter="text file (*.txt)|*.txt|all files (*.*)|*.*";
   open.showdialog();
   textbox2.text=open.filename;
   openla = true;
  }
        //保存加密或者解密的文件
  private void button10_click(object sender, system.eventargs e)
  {
   try
   {
    save=new savefiledialog();
    save.filter="file text (*.txt)|*.txt|all file (*.*)|*.*";
    save.showdialog();
    textbox3.text=save.filename;
    savela = true;
   }
   catch
   {
    messagebox.show("請(qǐng)輸入文件名字！");
    return;
   }

  }
  
        //加密文本文件
  private void button11_click(object sender, system.eventargs e)
  {
   if(readpubkey != true)
   {
    messagebox.show("請(qǐng)打開公鑰所在的文件！");
    return;
   }
   if(openla==true&&savela==true)
   {
    crypt=new rsacryptoserviceprovider();
    crypt.fromxmlstring( readpublickey );
    utf8encoding enc=new utf8encoding();
    //讀取原文件到一個(gè)string 去啊
    streamreader sr=new streamreader(textbox2.text,encoding.default);
    string textinfo=sr.readtoend();
    sr.close();
  //  richtext4.appendtext( "/n原文件內(nèi)容：/n" + textinfo + "/n" );
    //開始加密
    string readinfo=encryptfile(textinfo,textbox3.text);
    richtext4.appendtext( "加密文件已經(jīng)保存到：" + textbox3.text + "/n"  );
    richtext4.appendtext( "加密結(jié)果：/n" + readinfo + "/n加密結(jié)束！" ); 
   }
   else   
    messagebox.show("請(qǐng)選擇你要加密的文件或者要保存的文件！");   
  }
        //解密文件
  private void button12_click(object sender, system.eventargs e)
  {
   if(readprikey==false)
   {
    messagebox.show("請(qǐng)打開密匙所在的文件！");
    return;
   }
   if(openla==true&&savela==true)
   {
    try
    {
     crypt=new rsacryptoserviceprovider();
     crypt.fromxmlstring( readprivatekey );
     string decryptinfo = decryptfile(textbox2.text,textbox3.text);
     richtext4.appendtext( "解密文件已經(jīng)保存到：" + textbox3.text+ "/n" );
     richtext4.appendtext("解密結(jié)果：/n" + decryptinfo + "/n" + "解密結(jié)束！/n");
    }
    catch
    {
     messagebox.show("請(qǐng)檢查密匙文件是否和公匙相對(duì)應(yīng)或者密匙文件損壞！");
     return;
    }
   }
   else
    messagebox.show("請(qǐng)選擇你要解密的文件或者要保存的文件！");
  }
 
        //加密文件時(shí)候，同樣要打開公鑰匙
  private void button13_click(object sender, system.eventargs e)
  {   
   readpublickey = readpublickey();
   readpubkey=true;
 
  }
        //解密文件時(shí)候，同樣要打開私鑰匙
  private void button14_click(object sender, system.eventargs e)
  {   
   readprivatekey  =readprivatekey();
   readprikey=true; 
  }
  private void button15_click(object sender, system.eventargs e)
  {
   richtext4.clear();  
  }
 
       //打開文件 
  private void button16_click(object sender, system.eventargs e)
  {
   open = new openfiledialog( );
   open.filter="all files (*.*)|*.*";
   open.showdialog();
   textbox4.text=open.filename;
   openla = true; 
  }
  //保存文件
  private void button17_click(object sender, system.eventargs e)
  {
   save=new savefiledialog();
   save.filter="all file (*.*)|*.*";
   save.showdialog();
   textbox5.text=save.filename;
   savela = true;
  }
 

         //讀取公鑰匙
  private void button18_click(object sender, system.eventargs e)
  {
   readpublickey = readpublickey();
   readpubkey=true; 
  }  
        //讀取私鑰匙  
  private void button19_click(object sender, system.eventargs e)
  {
   readprivatekey = readprivatekey();
   readprikey=true; 
  }
        // 加密其它非文本文件啦
  private void button20_click(object sender, system.eventargs e)
  {
   if(readpubkey==false)
   {
    messagebox.show("請(qǐng)打開公匙所在的文件！");
    return;
   }
   if(openla==true&&savela==true)
   {
    try
    {
     crypt=new rsacryptoserviceprovider();
     crypt.fromxmlstring( readpublickey );
     encryptother( textbox4.text,textbox5.text );
     richtext5.appendtext("加密過程結(jié)束！：/n" + "加密文件已經(jīng)保存到：/n" + textbox5.text + "/n");
    }
    catch
    {
     messagebox.show("請(qǐng)檢查密匙文件是否和公匙相對(duì)應(yīng)或者密匙文件損壞！");
     return;
    }
   }
   else
    messagebox.show("請(qǐng)選擇你要解密的文件或者要保存的文件！");
 
  }
        //解密其它文件啦
  private void button21_click(object sender, system.eventargs e)
  {
   if(readprikey==false)
   {
    messagebox.show("請(qǐng)打開密匙所在的文件！");
    return;
   }
   if(openla==true&&savela==true)
   {
    try
    {
     crypt=new rsacryptoserviceprovider();
     crypt.fromxmlstring( readprivatekey );
     //使用線程后，反而達(dá)不到效果             //原因？暫時(shí)不清晰
     //可以轉(zhuǎn)換，但是轉(zhuǎn)換要經(jīng)過幾分鐘，才可以真正得到想要的轉(zhuǎn)換的東西。
     th = new thread( new threadstart(  decryptusingthread ) );
     th.start();
    // decryptother(textbox4.text,textbox5.text);    
     richtext5.appendtext( "解密結(jié)束！/n" + "解密文件已經(jīng)保存到：" + textbox5.text+ "/n" );    
    }
    catch
    {
     messagebox.show("請(qǐng)檢查密匙文件是否和公匙相對(duì)應(yīng)或者密匙文件損壞！");
     return;
    }
   }
   else
    messagebox.show("請(qǐng)選擇你要解密的文件或者要保存的文件！"); 
  }

  //下面為自己定義的函數(shù)啦
  //單獨(dú)一個(gè)讀取公匙的函數(shù)
  private string readpublickey()
  {
   
   string publickey;
   open = new openfiledialog( );
   open.filter="text file (*.txt)|*.txt|all file (*.*)|*.* ";
   open.showdialog();  
   streamreader sr = new streamreader(open.filename,utf8encoding.utf8);  
   publickey = sr.readtoend();
   sr.close();
   return publickey;  
  }
  //單獨(dú)一個(gè)讀取私匙的函數(shù)
  private string readprivatekey()
  {
   string privatekey;   
   open = new openfiledialog( );
   open.filter="text file (*.txt)|*.txt|all file (*.*)|*.* ";
   open.showdialog();
   streamreader sr = new streamreader(open.filename,utf8encoding.utf8);
   privatekey  = sr.readtoend();
   sr.close();  
   return privatekey;
  }
  //加密文本文件 
  private string encryptfile( string textinfo, string filename )
  {    
   utf8encoding enc=new utf8encoding();  
   byte [] bytes=enc.getbytes( textinfo );
   int blocksize=0;
   if(crypt.keysize==1024)
    blocksize=16;
   else
    blocksize=8;
   //同時(shí)寫入到內(nèi)存中去
   memorystream ms=new memorystream();
   //寫入文件中去啊。
   filestream fs=new filestream(@filename,filemode.openorcreate);
   byte[]rawblock,encryblock;
   for(int i=0;i<bytes.length;i+=blocksize)
   {
    if((bytes.length-i)>blocksize)
     rawblock=new byte[blocksize];
    else
     rawblock =new byte[bytes.length-i];
    buffer.blockcopy(bytes,i,rawblock,0,rawblock.length);
    encryblock=crypt.encrypt(rawblock,false);   
    fs.write(encryblock,0,encryblock.length);
    //寫入到內(nèi)存中去啊。
    ms.write(encryblock,0,encryblock.length);
   }
   //寫入到內(nèi)存中
   ms.position = 0;
   byte [] decode = new byte[ms.length];
   ms.read(decode,0,(int)ms.length);
   string decodeinfo = enc.getstring(decode,0,decode.length);  
   fs.flush();
   fs.close();
   ms.close();  
   return decodeinfo;
  }

  //解密文本文件
  private string decryptfile(string encryptfile,string decryptfile)
  {
   //打開加密后的文件，讀取文件內(nèi)容
   filestream fs=new filestream(@encryptfile,filemode.open);
   byte [] bytes=new byte[fs.length];
   fs.read(bytes,0,(int)fs.length);
   fs.close();
   //先寫入到內(nèi)存
   memorystream ms=new memorystream();
   //最好寫入到解密后的一個(gè)文件
   streamwriter sw=new streamwriter(decryptfile);
   int keysize=crypt.keysize/8;
   byte[]rawblock,decryptblock;
   for(int i=0;i<bytes.length;i+=keysize)
   {
    if( ( bytes.length-i ) > keysize )
    {
     rawblock=new byte[keysize];
    }
    else
    {rawblock =new byte[bytes.length-i];}

    buffer.blockcopy(bytes,i,rawblock,0,rawblock.length);
    decryptblock = crypt.decrypt( rawblock,false );
    ms.write(decryptblock,0,decryptblock.length);
   }
   ms.position=0;
   byte [] decode=new byte[ms.length];
   ms.read(decode,0,(int)ms.length);
   utf8encoding enc=new utf8encoding();
   string text=enc.getstring(decode);
   //寫入到內(nèi)存中去啊
   sw.write(text);
   sw.flush(); 
   ms.close();
   sw.close();
   return text;
  }

  //加密其它非文本文件，當(dāng)然可以包括文本文件
  private void encryptother(string file1,string file2)
  {
   filestream picfs=new filestream(@file1,filemode.open);
   filestream fs=new filestream(@file2,filemode.openorcreate);
   byte [] bytes=new byte[picfs.length];
   picfs.read(bytes,0,(int)picfs.length);
   picfs.close();
   int blocksize=0;
   if(crypt.keysize==1024)
    blocksize=16;
   else blocksize=8;  
   byte[]rawblock,encryblock;
   for(int i=0;i<bytes.length;i+=blocksize)
   {
    if((bytes.length-i)>blocksize)
     rawblock=new byte[blocksize];
    else rawblock =new byte[bytes.length-i];
    buffer.blockcopy(bytes,i,rawblock,0,rawblock.length);
    encryblock=crypt.encrypt(rawblock,false);
    fs.write(encryblock,0,encryblock.length);
   }
   fs.flush();
   fs.close();
  }
  //解密其它非文本文件，當(dāng)然可以包括文本文件
  private void decryptother(string fileone,string filetwo)
  {
   filestream fs=new filestream(@fileone,filemode.open);
   filestream writopic=new filestream(@filetwo,filemode.create);
   byte [] bytes=new byte[fs.length];
   fs.read(bytes,0,(int)fs.length);
   fs.close();
   memorystream ms=new memorystream();
   int keysize=crypt.keysize/8;
   byte[]rawblock,decryptblock;
   for(int i=0;i<bytes.length;i+=keysize)
   {
    if( ( bytes.length-i ) > keysize )
    {
     rawblock=new byte[keysize];
    }
    else
    {rawblock =new byte[bytes.length-i];}

    buffer.blockcopy(bytes,i,rawblock,0,rawblock.length);
    decryptblock = crypt.decrypt( rawblock,false );
    ms.write(decryptblock,0,decryptblock.length);
   }
   ms.position=0;
   byte [] decode=new byte[ms.length];
   ms.read(decode,0,(int)ms.length);
   ms.close();          
   writopic.write(decode,0,decode.length);
   writopic.close();

  }
  //創(chuàng)建一個(gè)函數(shù)，可以在線程中使用，經(jīng)實(shí)驗(yàn)，效果不明顯
  private void decryptusingthread()
  {
   decryptother(textbox4.text,textbox5.text);
  }
     
 }
}