borrow.cls

图书管理系统,采用VB+SQL,含最好的代码和数据库备份.

VERSION 1.0 CLASS
BEGIN
  MultiUse = -1  'True
  Persistable = 0  'NotPersistable
  DataBindingBehavior = 0  'vbNone
  DataSourceBehavior  = 0  'vbNone
  MTSTransactionMode  = 0  'NotAnMTSObject
END
Attribute VB_Name = "Borrow"
Attribute VB_GlobalNameSpace = False
Attribute VB_Creatable = True
Attribute VB_PredeclaredId = False
Attribute VB_Exposed = False
Public BorrowNo As String
Public Cardno As String
Public BorrowDate As String

Public Sub Init()
  BorrowNo = ""
  Cardno = ""
  BorrowDate = Date
End Sub

'删除借阅记录，同时删除借阅明细。只有所有借阅图书都归还，方可删除
Public Sub Delete(ByVal TmpBNo As String)
  SqlStmt = "DELETE FROM Borrow WHERE BorrowNo='" + Trim(TmpBNo) + "'"
  SQLExt (SqlStmt)
  '删除明细
  MyBorrowList.DeleteByBNo (TmpBNo)
End Sub

Public Function GetInfo(ByVal TmpBNo As String) As Boolean
  If Trim(TmpBNo) = "" Then
    GetInfo = False
    Init
    Exit Function
  End If
  
  BorrowNo = TmpBNo
  Dim rs As New ADODB.Recordset
  
  SqlStmt = "SELECT * FROM Borrow WHERE BorrowNo='" + Trim(TmpBNo) + "'"
  Set rs = QueryExt(SqlStmt)
  If rs.EOF Then
    GetInfo = False
    Init
    Exit Function
  Else
    If IsNull(rs.Fields(1)) Then
      Cardno = ""
    Else
      Cardno = Trim(rs.Fields(1))
    End If
    If IsNull(rs.Fields(2)) Then
      BorrowDate = ""
    Else
      BorrowDate = Trim(rs.Fields(2))
    End If
  End If
  GetInfo = True
End Function
'取得表中最大的借阅编号
Public Function GetMaxNo() As String
  Dim rs As New ADODB.Recordset
  
  SqlStmt = "SELECT MAX(Right(BorrowNo,3)) FROM Borrow"
  Set rs = QueryExt(SqlStmt)
  If Not IsNull(rs.Fields(0)) Then
    GetMaxNo = rs.Fields(0)
  Else
    GetMaxNo = "001"
  End If
End Function
Public Function In_DB(ByVal TmpBNo As String) As Boolean
  If Trim(TmpBNo) = "" Then
    In_DB = False
    Init
    Exit Function
  End If
  
  Dim rs As New ADODB.Recordset
  
  SqlStmt = "SELECT * FROM Borrow WHERE BorrowNo='" + Trim(TmpBNo) + "'"
  Set rs = QueryExt(SqlStmt)
  If Not rs.EOF Then
    In_DB = True
  Else
    In_DB = False
  End If
End Function

Public Sub Insert()
  SqlStmt = "INSERT INTO Borrow(BorrowNo,CardNo,BorrowDate) Values('" + Trim(BorrowNo) + "','" _
     + Trim(Cardno) + "','" + Trim(BorrowDate) + "')"
  SQLExt (SqlStmt)
End Sub

Public Sub Update(ByVal TmpBNo As String)
  SqlStmt = "Update Borrow Set Cardno='" + Trim(Cardno) + "'" _
          + " WHERE BorrowNo='" + Trim(TmpBNo) + "'"
  SQLExt (SqlStmt)
End Sub