• SQLite数据库的增删改查


    1、数据库的CURD

      1 public class PersonDao {
      2     private static final String TAG = "PersonDao";
      3     private MyDBOpenHelper dbOpenHelper;
      4 
      5     // 在personDao被new出来的时候 就完成初始化
      6 
      7     public PersonDao(Context context) {
      8         dbOpenHelper = new MyDBOpenHelper(context);
      9         // dbOpenHelper.getReadableDatabase()
     10         // dbOpenHelper.getWritableDatabase()
     11     }
     12 
     13     // 增删改查
     14 
     15     /**
     16      * 往数据库添加一条数据
     17      */
     18     public void add(String name, String phone) {
     19         boolean result = find(name);
     20         if (result)
     21             return;
     22 
     23         SQLiteDatabase db = dbOpenHelper.getWritableDatabase();
     24         if (db.isOpen()) {
     25             db.execSQL("insert into person (name,phone) values (?,?)",
     26                     new Object[] { name, phone });
     27             // 关闭数据库 释放数据库的链接
     28             db.close();
     29         }
     30     }
     31 
     32     /**
     33      * 查找数据库的操作
     34      */
     35     public boolean find(String name) {
     36         boolean result = false;
     37         SQLiteDatabase db = dbOpenHelper.getReadableDatabase();
     38         if (db.isOpen()) {
     39             Cursor cursor = db.rawQuery("select * from person where name=?",
     40                     new String[] { name });
     41             if (cursor.moveToFirst()) {
     42                 int index = cursor.getColumnIndex("phone"); // 得到phone在表中是第几列
     43                 String phone = cursor.getString(index);
     44                 Log.i(TAG, "phone =" + phone);
     45                 result = true;
     46 
     47             }
     48             // 记得关闭掉 cursor
     49             cursor.close();
     50             result = false;
     51             // 释放数据库的链接
     52             db.close();
     53         }
     54         return result;
     55     }
     56 
     57     /**
     58      * 删除一条记录
     59      * 
     60      * @param name
     61      */
     62     public void delete(String name) {
     63         SQLiteDatabase db = dbOpenHelper.getWritableDatabase();
     64         if (db.isOpen()) {
     65             db.execSQL("delete from person where name =?",
     66                     new Object[] { name });
     67             db.close();
     68         }
     69     }
     70 
     71     /**
     72      * 更新一条记录
     73      * 
     74      */
     75     public void update(String name, String newname, String newphone) {
     76         SQLiteDatabase db = dbOpenHelper.getWritableDatabase();
     77         if (db.isOpen()) {
     78             db.execSQL("update person set name=? , phone=? where name=?",
     79                     new Object[] { newname, newphone, name });
     80             db.close();
     81         }
     82     }
     83 
     84     /**
     85      * 查找全部
     86      */
     87     public List<Person> getAllPersons() {
     88         List<Person> persons=null;
     89         SQLiteDatabase db = dbOpenHelper.getReadableDatabase();
     90         if (db.isOpen()) {
     91             persons = new ArrayList<Person>();
     92             Cursor cursor = db.rawQuery("select * from person ", null);
     93             while (cursor.moveToNext()) {
     94                 Person person = new Person();
     95                 int nameindex = cursor.getColumnIndex("name");
     96                 int phoneindex = cursor.getColumnIndex("phone");
     97                 String name = cursor.getString(nameindex);
     98                 String phone = cursor.getString(phoneindex);
     99                 person.setName(name);
    100                 person.setNumber(phone);
    101                 persons.add(person);
    102             }
    103             cursor.close();
    104             db.close();
    105         }
    106         return persons;
    107     }
    108 
    109 }

    2、用junit测试

     1 public class TestPersonDao extends AndroidTestCase {
     2     PersonDao dao;
     3     // 测试在执行测试代码时候的流程 
     4     //1 .new TestPersonDao 框架new出来 
     5     //2. 调用 setUp()
     6     //3. testAdd()  这个时候 上下文 才被创建出来 
     7     
     8     
     9 /*    @Override
    10     protected void setUp() throws Exception {
    11         dao = new PersonDao(getContext());
    12         super.setUp();
    13     }*/
    14     public void testAdd() throws Exception{
    15         PersonDao dao = new PersonDao(getContext());
    16         for(int i=0;i<100;i++){
    17         dao.add("lisi"+i, "123456789"+i);
    18         }
    19     }
    20     public void testdelete() throws Exception{
    21         PersonDao dao = new PersonDao(getContext());
    22         dao.delete("lisi99");
    23     }
    24     public void testupdate() throws Exception{
    25         PersonDao dao = new PersonDao(getContext());
    26         dao.update("lisi98", "wangwu", "119");
    27     }
    28     
    29     public void testFindAll() throws Exception{
    30         PersonDao dao = new PersonDao(getContext());
    31         List<Person>  persons  = dao.getAllPersons();
    32         assertEquals(100, persons.size());
    33     }
    34  }

    使用junit步骤:

    1 Adndroid-Junit
    2 1、AndroidManifest.xml添加
    3 <instrumentation 
    4   android:name="android.test.InstrumentationTestRunner"
    5   android:targetPackage="cn.zengfansheng.db"
    6 />
    7 2、<application>添加节点
    8   <uses-library android:name="android.test.runner"/>
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  • 原文地址:https://www.cnblogs.com/hacket/p/3114460.html
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