关于md5加密介绍

MD5加密具体操作流程：

    下载地址的文档，有需要的可以参考一下：http://download.csdn.net/detail/u014608640/7189451

使用方法： 1.把工程中的MyMD5.h和MyMD5.m文件加入你的工程中 2.在你的类中导入 #import “MyMD5.h” 3.调用MyMD5的类方法 [MyMD5 md5:@“testText”];

 

java代码： package eoe.md5demo;  import android.app.Activity;  import android.os.Bundle;  public class Login extends Activity {  @Override  protected void onCreate(Bundle savedInstanceState) {  // TODO Auto-generated method stub  super.onCreate(savedInstanceState);  setContentView(R.layout.login);  }  }  MD5Demo.java java代码： package eoe.md5demo;  import java.security.MessageDigest;  import android.app.Activity;  import android.content.Intent;  import android.content.SharedPreferences;  import android.os.Bundle;  import android.view.View;  import android.widget.Button;  import android.widget.EditText;  import android.widget.Toast;  public class MD5Demo extends Activity {  private EditText username,password;  private Button savebtn,loginbtn;  String user,pass;  @Override 

public void onCreate(Bundle savedInstanceState) {  super.onCreate(savedInstanceState);  setContentView(R.layout.main);  username = (EditText)findViewById(R.id.username);  password = (EditText)findViewById(R.id.password);  savebtn = (Button)findViewById(R.id.save);  loginbtn = (Button)findViewById(R.id.login);  savebtn.setOnClickListener(new Button.OnClickListener(){  @Override  public void onClick(View v) {  SharedPreferences pre = getSharedPreferences("loginvalue",MODE_WORLD_WRITEABLE);  pass = MD5(password.getText().toString());  user = username.getText().toString();  if(!pass.equals("")&&!user.equals("")){  pre.edit().putString("username", username.getText().toString()).  putString("password",encryptmd5(pass)).commit();  Toast.makeText(getApplicationContext(), "保存成功!", Toast.LENGTH_SHORT).show();  }else{  Toast.makeText(getApplicationContext(), "密码不能为空！", Toast.LENGTH_LONG).show();  }  }  }); 

loginbtn.setOnClickListener(new Button.OnClickListener(){  @Override  public void onClick(View v) {  SharedPreferences sp = getSharedPreferences("loginvalue", MODE_WORLD_READABLE);  String loginuser = sp.getString("username", null);  String loginpass = sp.getString("password", null);  user = username.getText().toString();  pass = password.getText().toString();  String passmd5 = MD5(pass);  String encryptmd5 = encryptmd5(passmd5);  System.out.println("username="+loginuser+"-------------password="+loginpass);  System.out.println("user=="+user+"-------------encryptmd5=="+encryptmd5);  if(!user.equals("")&&!pass.equals(""))  {  if( user.equals(loginuser)&& encryptmd5.equals(loginpass))  {  Intent intent = new Intent();  intent.setClass(MD5Demo.this, Login.class);  MD5Demo.this.startActivity(intent);  finish();  }else{  Toast.makeText(getApplicationContext(), "密码是错误的！", Toast.LENGTH_LONG).show();  }  }else{  Toast.makeText(getApplicationContext(), "密码不能为空！", Toast.LENGTH_LONG).show();  }  }  });  } 

 

//MD5加密，32位  public static String MD5(String str){  MessageDigest md5 = null;  try{  md5 = MessageDigest.getInstance("MD5");  }catch(Exception e){  e.printStackTrace();  return "";  }  char[] charArray = str.toCharArray();  byte[] byteArray = new byte[charArray.length];  for(int i = 0; i < charArray.length; i++){  byteArray[i] = (byte)charArray[i];  }  byte[] md5Bytes = md5.digest(byteArray);  StringBuffer hexValue = new StringBuffer();  for( int i = 0; i < md5Bytes.length; i++)  {  int val = ((int)md5Bytes[i])&0xff;  if(val < 16)  {  hexValue.append("0");  }  hexValue.append(Integer.toHexString(val));  }  return hexValue.toString();  }  // 可逆的加密算法  public static String encryptmd5(String str) {  char[] a = str.toCharArray();  for (int i = 0; i < a.length; i++)  {  a[i] = (char) (a[i] ^ 'l');  }  String s = new String(a);  return s;  }  }