frmreturn.frm

第一次用VB编写的图书管理系统,仅供大家参考,呵呵,不足之处多多包含

VERSION 5.00
Begin VB.Form FrmReturn 
   Caption         =   "还 书"
   ClientHeight    =   1275
   ClientLeft      =   60
   ClientTop       =   345
   ClientWidth     =   3510
   LinkTopic       =   "Form1"
   MaxButton       =   0   'False
   MDIChild        =   -1  'True
   ScaleHeight     =   1275
   ScaleWidth      =   3510
   Begin VB.TextBox txt 
      ForeColor       =   &H00FF0000&
      Height          =   270
      Left            =   1080
      TabIndex        =   0
      Top             =   240
      Width           =   2055
   End
   Begin VB.CommandButton cmdR 
      Caption         =   "确认(&O)"
      Enabled         =   0   'False
      Height          =   375
      Index           =   0
      Left            =   240
      TabIndex        =   3
      Top             =   720
      Width           =   1335
   End
   Begin VB.CommandButton cmdR 
      Cancel          =   -1  'True
      Caption         =   "返回(&R)"
      Height          =   375
      Index           =   1
      Left            =   1920
      TabIndex        =   2
      Top             =   720
      Width           =   1335
   End
   Begin VB.Label Label1 
      AutoSize        =   -1  'True
      Caption         =   "图书编号"
      ForeColor       =   &H8000000D&
      Height          =   180
      Left            =   240
      TabIndex        =   1
      Top             =   285
      Width           =   720
   End
End
Attribute VB_Name = "FrmReturn"
Attribute VB_GlobalNameSpace = False
Attribute VB_Creatable = False
Attribute VB_PredeclaredId = True
Attribute VB_Exposed = False
Private Sub cmdR_Click(Index As Integer)
On Error GoTo R_Err:
If Index = 1 Then Unload Me: Exit Sub
Call QueryInfo("select case when (reborrow='否' and datediff(day,borrowdate,getdate())<=30 )" & _
      "     or (reborrow='是' and datediff(day,borrowdate,getdate())<=15 ) " & _
      "   then datediff(day,borrowdate,getdate()) " & _
      " when reborrow='否'and datediff(day,borrowdate,getdate())>30" & _
      " then 30-datediff(day,borrowdate,getdate())" & _
      " else 15-datediff(day,borrowdate,getdate()) End " & _
      " from borrow where returndate is null and bookid='" & Choose(Txt) & "'")
 If DBRct.EOF Then GoTo R_Err
 DBRct.MoveFirst
If DBRct.Fields(0) < 0 Then
   Call ExecuteSQL("update readers set publish=publish+" & -DBRct.Fields(0) * 0.2 & " where readerid in (select readerid from " & _
                    "borrow where returndate is null and bookid='" & Choose(Txt) & "')")
 End If
Call ExecuteSQL("update borrow set returndate=getdate(),reborrow='已还' where returndate is null and bookid='" & Choose(Txt) & "'")
Call QueryInfo("select * from books where bookid='" & Choose(Txt) & "'")
MsgBox "图书:" & DBRct.Fields("bookname").Value & vbCrLf & "还书成功！", vbInformation, "成功"
Txt = Empty
Exit Sub
R_Err:
MsgBox "该书未被借或根本没有该书！", vbInformation, "还书失败"
End Sub

Private Sub Form_Resize()
If Me.Height <= 500 Or Me.Width <= 1500 Then Exit Sub
Me.Height = 1680
Me.Width = 3630
End Sub

Private Sub txt_Change()
If Txt = Empty Then cmdR(0).Enabled = False Else cmdR(0).Enabled = True
End Sub

Private Sub txt_KeyPress(KeyAscii As Integer)
If Txt <> Empty And KeyAscii = 13 Then cmdR_Click (0)
End Sub