Android数据库实验

1、精选优质文档-倾情为你奉上实验报告实验项目：Android数据库实验一、实验目的1、理解Android中常用的数据存储方式及各自特点；2、掌握Sqlite数据库的相关操作；3、掌握编程访问Sqlite数据库的方法；二、实验原理1、数据存储方式：SharedPreferences、文件、数据库等；2、Sqlite数据库访问；三、实验步骤、数据记录及处理1、手动操作Sqlite数据库；2、编程访问Sqlite数据库，实验用户登录、注册等基本功能；1.定义数据库MySQLiteOpenHelper继承父类SQLiteOpenHelper写基本操作要用的方法并建立相关的类。相关代码如下：MySQLit

2、eOpenHelper.java:public class MySQLiteOpenHelper extends SQLiteOpenHelper public static final String DATABASE_NAME = S.db; public static final String TABLE_NAME = S_table; public static final String COL_1 = ID; public static final String COL_2 = NAME; public static final String COL_3 = PASSWORD; pub

3、lic MySQLiteOpenHelper(Context contect) super(contect, DATABASE_NAME, null, 1); Override public void onCreate(SQLiteDatabase db) db.execSQL(CREATE TABLE + TABLE_NAME + (ID INTEGER PRIMARY KEY AUTOINCREMENT,NAME TEXT,PASSWORD TEXT); Override public void onUpgrade(SQLiteDatabase db, int oldVersion, in

4、t newVersion) db.execSQL(DROP TABLE IF EXISTS + TABLE_NAME); public Integer deleteData(String id) SQLiteDatabase db = this.getWritableDatabase(); int i = db.delete(TABLE_NAME, ID=?, new Stringid); return i; public boolean find(User userpeople) SQLiteDatabase db = this.getWritableDatabase(); User use

5、r =queryAllData(); if(user=null)return false; for(User i:user) if(.equals()& i.password.equals(userpeople.password) return true; return false; public User queryAllData() SQLiteDatabase db = this.getWritableDatabase(); Cursor results = db.query(TABLE_NAME, new String COL_1,COL_2,

6、 COL_3,null,null,null,null,null); return ConvertToPeople(results); private User ConvertToPeople(Cursor cursor) int resultCounts = cursor.getCount(); if (resultCounts = 0 | !cursor.moveToFirst() return null; User user = new UserresultCounts; for (int i = 0 ; iresultCounts; i+) useri = new User(); use

7、 = cursor.getString(cursor.getColumnIndex(COL_2); useri.password = cursor.getString(cursor.getColumnIndex(COL_3); cursor.moveToNext(); return user; public boolean insertData(String name, String password) SQLiteDatabase db = this.getWritableDatabase(); /打开数据库 ContentValues contentValues = new

8、ContentValues(); contentValues.put(COL_2, name); contentValues.put(COL_3, password); long result = db.insert(TABLE_NAME, null, contentValues); db.close(); if (result = -1) return false; else return true; User.java:public class User private static final long serialVersionUID = 1L; public String name;

9、 public String password; public User() public User(String name, String password) super(); = name; this.password = password; public String getName() return name; public void setName(String name) = name; public String getPassword() return password; public void setPassword(String pa

10、ssword) this.password = password; Override public String toString() return User name= + name + , password= + password + ; 用cmd命令查看在注册界面输入的用户名和密码已经被正确的存入数据库中，操作如下图：2.实现登陆注册的验证。验证界面的数据已经存入数据库中，要完成验证我们需要把用户在登陆界面输入的用户名和密码获取到并和数据库中的数据进行比对，结果会有两种情况：1. 信息完全匹配，界面下方显示Toast登陆成功；2. 信息有至少一条不匹配，界面下方显示Toast登陆失败；相

11、关代码如下：RegisterActivity.java:/定义数据库需要控件(INSERT)myDb = new MySQLiteOpenHelper(this);textName=(EditText)findViewById(R.id.ideText3);textPassword=(EditText)findViewById(R.id.ideText4);Button button4 = (Button)findViewById(R.id.button4);button4.setOnClickListener(new View .OnClickListener() Override publ

12、ic void onClick(View v) ClickMe(); );/添加数据入数据库(INSERT)private void ClickMe() String new_name = textName.getText().toString(); String new_password = textPassword.getText().toString(); Boolean result = myDb.insertData(new_name,new_password); if(result = true) Toast.makeText(this, Data Inserted Sucessf

13、ully, Toast.LENGTH_SHORT).show(); else Toast.makeText(this, Data Inserted Failed, Toast.LENGTH_SHORT).show(); MainActivity.java:/登陆Button button1 = (Button) findViewById(R.id.button1);button1.setOnClickListener(new View.OnClickListener() Override public void onClick(View v) /点击登录按钮 _name = (EditText

14、) findViewById(R.id.et1); _password = (EditText) findViewById(R.id.et2); User user = new User(_name.getText().toString(),_password.getText().toString(); /String log_name = _name.getText().toString(); /String log_password = _password.getText().toString(); if(myDb.find(user)=true) Toast.makeText(getApplicationContext(), 登录成功, Toast.LENGTH_SHORT).show(); else Toast.makeText(getApplicationContext(), 登录失败, Toast.LENGTH_SHORT).show(); );/验证登录public boolean login(String username,String password) SQLiteDatabase db = myDb.getW