Android掌上点餐系统

package cn.iimob.waiters.db; import android.content.ContentValues; import android.content.Context; import android.database.Cursor; import android.database.sqlite.SQLiteDatabase; import android.database.sqlite.SQLiteOpenHelper; public class DB_Table_Number extends SQLiteOpenHelper { private static final String DB_NAME = "tablenumber.db"; private static final String TBL_NAME = "TableNumber"; private static final String CREATE_TBL = " create table " + " TableNumber(_id integer primary key autoincrement,number text) "; static String tempall=""; private SQLiteDatabase db; public DB_Table_Number(Context c) { super(c, DB_NAME, null, 2); } public void onCreate(SQLiteDatabase db) { this.db = db; db.execSQL(CREATE_TBL); } public void insert(ContentValues values) { SQLiteDatabase db = getWritableDatabase(); db.insert(TBL_NAME, null, values); db.close(); } public Cursor query() { SQLiteDatabase db = getWritableDatabase(); Cursor c = db.query(TBL_NAME, null, null, null, null, null, null); return c; } public String select(String s){ SQLiteDatabase db = getWritableDatabase(); String sql="select *from TableNumber " + "where number='"+s+"'"; Cursor cursor=db.rawQuery(sql, null); if (cursor != null) { String temp = ""; int i = 0; while (cursor.moveToNext()) { temp+=cursor.getString(0); } tempall=temp; cursor.close(); } return tempall; } public void delete(String s) { SQLiteDatabase db = getWritableDatabase(); String sql="delete from TableNumber " + "where number='"+s+"'"; db.execSQL(sql); } public void close() { if (db != null) db.close(); } public void clean (){ this.getWritableDatabase().execSQL("DROP TABLE IF EXISTS "+TBL_NAME); this.onCreate(this.getWritableDatabase()); this.getWritableDatabase().close(); } @Override public void onUpgrade(SQLiteDatabase db, int oldVersion, int newVersion) { } }