SQliteB4A教程大苏营.doc

Basic4androidc操作 Sqlite 数据库教程 Step 1 ：操作环境需要有库SQL Library Step 2 : 创建数据库Database 2-1 创建一个code module 大概这个样子 2-2 声明 Sub Process_Globals These global variables will be declared once when the application starts. These variables can be accessed from all modules. Dim SQL_ite As SQL Dim DBFileName As String : DBFileName = mhbj130.db Dim DBFileDir As String : DBFileDir = File.DirInternal Dim DBFileDir As String : DBFileDir = File.DirRootExternal Dim DBTableName As String : DBTableName = mhbj130 2-3 在b4a_sqlite 上创建一个createdb sub Sub Create_db (FirstTime As Boolean) 数据库创建 File.MakeDir(File.DirRootExternal,mhbj) 创建目录 DBFileDir = File.DirRootExternal /mhbj If File.Exists(DBFileDir, DBFileName) = False Then If FirstTime Then Msgbox(第一次运行在你设备上先创建一个数据库文件,创建数据库) File.Copy(File.DirAssets, DBFileName, DBFileDir, DBFileName) SQL_ite.Initialize(DBFileDir, DBFileName, True) End If Else If FirstTime Then SQL_ite.Initialize(DBFileDir, DBFileName, False) End If End If End Sub 2-4 找一个空的数据库放到开发目录的files 并修改为你想要的数据库文件名,这个数据库文件第一次运行时会拷贝到手机的\mnt\sdcard\mhbj 目录下 Mhbj130.db 2-5 在main模块的Activity_Create()中调用 Sub Activity_Create(FirstTime As Boolean) 创建数据库 B4A_SQlite.create_db(FirstTime) 2-7 SQlite数据库第三方工具 SQLite Expert Step 3 创建表Table 3-1 创建create_table() Sub Create_Table(create_sql As String) SQL_ite.ExecNonQuery(create_sql) End Sub Step 4 查询数据 Select 4-1 先用SQLite Expert 输入几行模拟数据 4-2 在b4a_sqlite上创建查询sub 先声明一个游标接收返回结果集 Dim cur130 As Cursor Sub exec_Select (select_sql As String) cur130 = SQL_ite.ExecQuery(select_sql) End Sub 4-3 结果集显示在lv_main上 从游标cur130加载数据 Dim ls_name As String Dim ls_date As String ls_sql = select s_date,s_name from mhbj130 order by s_date desc B4A_SQLite.exec_Select(ls_sql) LV_main.TwoLinesAndBitmap.SecondLabel.Gravity = Gravity.RIGHT LV_main.TwoLinesAndBitmap.SecondLabel.Width = LV_main.Width - LV_main.TwoLinesAndBitmap.ImageView.Width - 10dip For ll = 0 To B4A_SQLite.cur130.RowCount - 1