3、 Add方法
Add方法的目的是向数据库中添加一条新的CD信息,因此它打开的记录集要求能够更新。这就不能像OpenDB中那样仅用Open打开数据集。详细的代码见下面:
Private Sub Add(Id As String, Name As String, Author As String, Price As Currency, Information As String)
Dim NewConn As New ADODB.Connection
Dim NewRecordsetCD As New ADODB.Recordset
NewConn.Open "Provider=SQLOLEDB;DataSource=MUSE;Initial Catalog=Music;UserId=Wayne;Password=AbCdEfG"
NewRecordsetCD.Open "SELECT * FROM CD", NewConn, adOpenDynamic, adLockOptimistic
NewRecordsetCD.AddNew
NewRecordsetCD.Fields("CD_ID") = Id
NewRecordsetCD.Fields("CD_Name") = Name
NewRecordsetCD.Fields("CD_Author") = Author
NewRecordsetCD.Fields("CD_Price") = Price
NewRecordsetCD.Fields("CD_Information") = Information
NewRecordsetCD.Update
End Sub
解释:使用 NewRecordsetCD.AddNew,
NewRecordsetCD.Fields(“Some_Key”)=Some_Value
NewRecordsetCD.Update 来添加一条纪录
4、 Delete方法:
这个方法的目的是为了删除库中的某条CD名和相关的信息。它的实现方法是通过查询表中唯一的CD_ID来定位CD信息,从而删除该行纪录
Private Sub Delete(Id As String)
Dim NewConn As New ADODB.Connection
Dim RecordsetDelete As New ADODB.Recordset
NewConn.Open "Provider=SQLOLEDB;DataSource=MUSE;Initial Catalog=Music;UserId=Wayne;Password=AbCdEfG"
’从表中删除一条信息
NewConn.Execute "DELETE FROM CD WHERE CD_ID ='" & Id & "'", adCmdText + adExecuteNoRecords
End Sub
……