rs_reader.Update DataGrid1.Refresh End Sub
Private Sub cmdupdate_Click()
If Not IsNull(DataGrid1.Bookmark) Then rs_reader.Update End If
cmdmodify.Enabled = True cmddel.Enabled = True cmdcancel.Enabled = False cmdupdate.Enabled = False DataGrid1.AllowUpdate = False
MsgBox \保存成功！\ End Sub
Private Sub Command1_Click() Unload Me End Sub
Private Sub Form_Load() Dim sql As String
On Error GoTo loaderror
sql = \读者信息\
rs_reader.CursorLocation = adUseClient
rs_reader.Open sql, conn, adOpenKeyset, adLockPessimistic '打开数据库 cmdupdate.Enabled = False '设定datagrid控件属性
DataGrid1.AllowAddNew = False '不可增加 DataGrid1.AllowDelete = False '不可删除 DataGrid1.AllowUpdate = False
If userpow = \ '权限相关 VB+Access图书管理系统
Private Sub Form_Unload(Cancel As Integer) Set DataGrid1.DataSource = Nothing rs_reader.Close End Sub
11、文件名 frmfindreader（frmfindreader.frm）
功能说明：查询读者信息，可以选择性的输入读者姓名、读者编号、读者种类来查询读者的详细信息。 源代码：
Option Explicit
Private Sub Command1_Click()
Dim rs_findreader As New ADODB.Recordset Dim sql As String
If Check1.Value = vbChecked Then
sql = \读者编号='\
End If
If Check2.Value = vbChecked Then If Trim(sql) = \
sql = \读者姓名='\ Else
sql = sql & \读者姓名='\ End If End If
If Check3.Value = vbChecked Then If Trim(sql) = \
sql = \读者类别='\ Else
sql = sql & \ 读者类别='\ End If End If
sql = \读者信息 where \ rs_findreader.CursorLocation = adUseClient
rs_findreader.Open sql, conn, adOpenKeyset, adLockPessimistic DataGrid1.AllowAddNew = False DataGrid1.AllowDelete = False DataGrid1.AllowUpdate = False
Set DataGrid1.DataSource = rs_findreader End Sub
Private Sub Command2_Click() Unload Me End Sub
Private Sub Form_Load()
Dim rs_find As New ADODB.Recordset Dim sql As String
sql = \读者类别\
rs_find.Open sql, conn, adOpenKeyset, adLockPessimistic If Not rs_find.EOF Then
Do While Not rs_find.EOF
Combo1.AddItem rs_find.Fields(0) rs_find.MoveNext Loop
Combo1.ListIndex = 0 End If
rs_find.Close End Sub
12、文件名 frmfindborrowinfo（frmfindborrowinfo.frm）
功能说明：查询借书信息，可以查询到已借出的书、未借出的图书。 源代码：
Option Explicit
Private Sub Command1_Click() Dim sql As String
Dim rs_find As New ADODB.Recordset If Option1.Value = True Then
sql = \书籍信息 where 是否被借出='是'\ End If
If Option2.Value = True Then
sql = \书籍信息 where 是否被借出='否'\ End If
If Option3.Value = True Then
sql = \借阅信息 where 读者姓名='\ End If
rs_find.CursorLocation = adUseClient
rs_find.Open sql, conn, adOpenKeyset, adLockPessimistic DataGrid1.AllowAddNew = False DataGrid1.AllowDelete = False DataGrid1.AllowUpdate = False Set DataGrid1.DataSource = rs_find End Sub
13、文件名 frmbackbookinfo（frmbackbookinfo.frm）
功能说明：添加还书信息，可以通过读者编号、读者姓名、图书编号、图书名称等查询到已借出的书。 源代码：
Option Explicit
Dim findform As Boolean Private Sub Combo1_Click()
Combo2.ListIndex = Combo1.ListIndex End Sub
Private Sub Command1_Click()
Dim rs_reader As New ADODB.Recordset Dim sql As String findform = True
sql = \借阅信息 where 读者姓名='\ rs_reader.CursorLocation = adUseClient
rs_reader.Open sql, conn, adOpenKeyset, adLockPessimistic Set DataGrid1.DataSource = rs_reader DataGrid1.AllowAddNew = False DataGrid1.AllowDelete = False DataGrid1.AllowUpdate = False End Sub
Private Sub Command2_Click()
Dim rs_book As New ADODB.Recordset Dim sql As String findform = False
sql = \借阅信息 where 书籍编号='\ rs_book.CursorLocation = adUseClient
rs_book.Open sql, conn, adOpenKeyset, adLockPessimistic Set DataGrid1.DataSource = rs_book DataGrid1.AllowAddNew = False DataGrid1.AllowDelete = False DataGrid1.AllowUpdate = False End Sub
Private Sub Command3_Click() Dim book_num As String Dim reader_num As String Dim answer As String
Dim rs_back As New ADODB.Recordset VB+Access图书管理系统 Dim sql As String
On Error GoTo delerror
book_num = DataGrid1.Columns(3).CellValue(DataGrid1.Bookmark) reader_num = DataGrid1.Columns(1).CellValue(DataGrid1.Bookmark) answer = MsgBox(\确定要还这本书吗？\ If answer = vbYes Then
sql = \借阅信息 where 书籍编号='\ rs_back.CursorLocation = adUseClient
rs_back.Open sql, conn, adOpenKeyset, adLockPessimistic rs_back.Delete rs_back.Update rs_back.Close
sql = \书籍信息 where 书籍编号='\ rs_back.CursorLocation = adUseClient
rs_back.Open sql, conn, adOpenKeyset, adLockPessimistic rs_back.Fields(7) = \否\ rs_back.Update rs_back.Close
sql = \读者信息 where 读者编号='\ rs_back.CursorLocation = adUseClient
rs_back.Open sql, conn, adOpenKeyset, adLockPessimistic rs_back.Fields(8) = rs_back.Fields(8) - 1 rs_back.Update rs_back.Close
If findform = True Then Command1_Click Else
Command2_Click End If
MsgBox \成功删除！\
DataGrid1.AllowDelete = False Else
Exit Sub End If delerror:
If Err.Number <> 0 Then MsgBox Err.Description End If
rs_reader.Close
sql = \借阅信息\
rs_book.CursorLocation = adUseClient
rs_book.Open sql, conn, adOpenKeyset, adLockPessimistic If Not rs_book.EOF Then
Do While Not rs_book.EOF
Combo3.AddItem rs_book.Fields(3) Combo4.AddItem rs_book.Fields(4) rs_book.MoveNext Loop End If
rs_book.Close End Sub