cardtype.cls

vb与access数据库的操作实例

VERSION 1.0 CLASS
BEGIN
  MultiUse = -1  'True
  Persistable = 0  'NotPersistable
  DataBindingBehavior = 0  'vbNone
  DataSourceBehavior  = 0  'vbNone
  MTSTransactionMode  = 0  'NotAnMTSObject
END
Attribute VB_Name = "CardType"
Attribute VB_GlobalNameSpace = False
Attribute VB_Creatable = True
Attribute VB_PredeclaredId = False
Attribute VB_Exposed = False
'1 Id  长整型 自动编号 编号
'2 TypeName  文本 50  分类名称
'3 MaxCount 数字 整型 最大借阅数量
'4 MaxDays 数字 整型 最多借阅天数
'5 AddDays 数字 整型 续借天数

Public Id As Long
Public TypeName As String
Public MaxCount As Integer
Public MaxDays As Integer
Public AddDays As Integer

Public Sub Init()
  Id = 0
  TypeName = ""
  MaxCount = 10
  MaxDays = 100
  AddDays = 30
End Sub

'删除CardType
Public Sub Delete(ByVal TmpId As Long)
  SqlStmt = "DELETE FROM CardType WHERE Id=" + Trim(Str(TmpId))
  SQLExt (SqlStmt)
End Sub

Public Function GetInfo(TmpId As Long) As Boolean
  If TmpId <= 0 Then
    Init
    GetInfo = False
    Exit Function
  End If
  Id = TmpId
  
  Dim rs As New ADODB.Recordset
  
  SqlStmt = "SELECT * FROM CardType WHERE Id=" + Trim(Str(TmpId))
  Set rs = QueryExt(SqlStmt)
  If Not rs.EOF Then
    If IsNull(rs.Fields(0)) Then
      Id = 0
    Else
      Id = Val(rs.Fields(0))
    End If
    If IsNull(rs.Fields(1)) Then
      TypeName = ""
    Else
      TypeName = rs.Fields(1)
    End If
    If IsNull(rs.Fields(2)) Then
      MaxCount = 10
    Else
      MaxCount = rs.Fields(2)
    End If
    If IsNull(rs.Fields(3)) Then
      MaxDays = 100
    Else
      MaxDays = rs.Fields(3)
    End If
    If IsNull(rs.Fields(4)) Then
      AddDays = 30
    Else
      AddDays = rs.Fields(4)
    End If
    GetInfo = True
  Else
    Init
    GetInfo = False
  End If
End Function

Public Function In_DB(ByVal TypeName As String) As Boolean
  Dim rs As New ADODB.Recordset
  
  SqlStmt = "SELECT Id FROM CardType WHERE TypeName='" _
          + Trim(TypeName) + "'"
  Set rs = QueryExt(SqlStmt)
  If Not rs.EOF Then
    In_DB = False
  Else
    In_DB = True
  End If
End Function

Public Sub Insert()
  SqlStmt = "INSERT INTO CardType(TypeName,MaxCount,MaxDays,AddDays)" _
          + " VALUES('" + Trim(TypeName) + "'," + Trim(MaxCount) _
          + "," + Trim(Str(MaxDays)) + "," + Trim(Str(AddDays)) + ")"
  SQLExt (SqlStmt)
End Sub

'更新数据
Public Sub Update(ByVal TmpId As Long)
  SqlStmt = "UPDATE CardType SET TypeName='" + Trim(TypeName) _
          + "',MaxCount=" + Trim(MaxCount) + ",MaxDays=" + Trim(MaxDays) _
          + ",AddDays=" + Trim(AddDays) + " WHERE Id=" + Trim(Str(TmpId))
  SQLExt (SqlStmt)
End Sub