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  • SQLite数据操作

    1. DataBaseOpenHelp:

     1 package com.vanceinfo.service;
    2
    3 import android.content.Context;
    4 import android.database.sqlite.SQLiteDatabase;
    5 import android.database.sqlite.SQLiteOpenHelper;
    6
    7 public class DataBaseOpenHelp extends SQLiteOpenHelper
    8 {
    9
    10 private static final String SQLITE_NAME = "itcast";
    11
    12 private static final int version = 1;
    13
    14 public DataBaseOpenHelp(Context context)
    15 {
    16 super(context, SQLITE_NAME, null, version);
    17
    18 }
    19
    20 @Override
    21 public void onCreate(SQLiteDatabase db)
    22 {
    23 db.execSQL("CREATE TABLE person (personid integer primary key autoincrement,name varchar(20),age INTEGER)");
    24 }
    25
    26 @Override
    27 public void onUpgrade(SQLiteDatabase db, int oldVersion, int newVersion)
    28 {
    29 db.execSQL("DROP TABLE IF EXISTS person");
    30 onCreate(db);
    31 }
    32
    33 }

    2. PersonService

      1 package com.vanceinfo.service;
    2
    3 import java.util.ArrayList;
    4 import java.util.List;
    5
    6 import android.content.Context;
    7 import android.database.Cursor;
    8 import android.database.sqlite.SQLiteDatabase;
    9
    10 import com.vanceinfo.domian.Person;
    11
    12 public class PersonService
    13 {
    14 private DataBaseOpenHelp dbOpenHelp;
    15
    16 public PersonService(Context context)
    17 {
    18 dbOpenHelp = new DataBaseOpenHelp(context);
    19 }
    20
    21 /**
    22 * 保存
    23 *
    24 * @param person
    25 */
    26 public void save(Person person)
    27 {
    28 SQLiteDatabase database = dbOpenHelp.getWritableDatabase();
    29 database.execSQL("insert into person(name,age) values(?,?)", new Object[] {person.getName(), person.getAge()});
    30 }
    31
    32 /**
    33 * 更新
    34 *
    35 * @param person
    36 */
    37 public void update(Person person)
    38 {
    39 SQLiteDatabase database = dbOpenHelp.getWritableDatabase();
    40 database.execSQL("update person set name=? ,age=? where personid=?",
    41 new Object[] {person.getName(), person.getAge(), person.getPersonid()});
    42 }
    43
    44 /**
    45 * 删除
    46 *
    47 * @param ids
    48 */
    49 public void delete(Integer... ids)
    50 {
    51 if (ids.length > 0)
    52 {
    53 StringBuilder sb = new StringBuilder();
    54 for (Integer id : ids)
    55 {
    56 sb.append('?').append(',');
    57 }
    58 sb.deleteCharAt(sb.length() - 1);
    59 SQLiteDatabase database = dbOpenHelp.getWritableDatabase();
    60 database.execSQL("delete from person where personid in(" + sb + ")", (Object[]) ids);
    61 }
    62 }
    63
    64 /**
    65 * 查询
    66 *
    67 * @param id
    68 * @return
    69 */
    70 public Person find(Integer id)
    71 {
    72 SQLiteDatabase database = dbOpenHelp.getWritableDatabase();
    73 Cursor cursor = database.rawQuery("select * from person where personid=?", new String[] {String.valueOf(id)});
    74 while (cursor.moveToNext())
    75 {
    76 return new Person(cursor.getInt(0), cursor.getString(1), cursor.getShort(2));
    77 }
    78 return null;
    79 }
    80
    81 /**
    82 * 条件查询
    83 *
    84 * @param start
    85 * @return
    86 */
    87 public List<Person> getScrollData(int startResult, int maxResult)
    88 {
    89 List<Person> persons = new ArrayList<Person>();
    90 SQLiteDatabase database = dbOpenHelp.getWritableDatabase();
    91 Cursor cursor = database.rawQuery("select * from person limit ?,?", new String[] {String.valueOf(startResult),
    92 String.valueOf(maxResult)});
    93 while (cursor.moveToNext())
    94 {
    95 persons.add(new Person(cursor.getInt(0), cursor.getString(1), cursor.getShort(2)));
    96 }
    97 return persons;
    98
    99 }
    100
    101 /**
    102 * 获得数量
    103 *
    104 * @return
    105 */
    106 public long getCount()
    107 {
    108 SQLiteDatabase database = dbOpenHelp.getWritableDatabase();
    109 Cursor cursor = database.rawQuery("select count(*) from person", null);
    110 if (cursor.moveToNext())
    111 {
    112 return cursor.getLong(0);
    113 }
    114 return 0;
    115
    116 }
    117
    118 public void drop()
    119 {
    120 SQLiteDatabase database = dbOpenHelp.getWritableDatabase();
    121 database.execSQL("drop table person");
    122 }
    123
    124 }




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  • 原文地址:https://www.cnblogs.com/jh5240/p/2229322.html
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