frmpasswd.frm

在VB中开发的连接SQL的图书管理系统。

VERSION 5.00
Begin VB.Form frmPasswd 
   BorderStyle     =   1  'Fixed Single
   Caption         =   "用户登录"
   ClientHeight    =   3090
   ClientLeft      =   45
   ClientTop       =   435
   ClientWidth     =   4680
   ControlBox      =   0   'False
   Icon            =   "frmPasswd.frx":0000
   LinkTopic       =   "Form1"
   MaxButton       =   0   'False
   MinButton       =   0   'False
   ScaleHeight     =   3090
   ScaleWidth      =   4680
   StartUpPosition =   2  '屏幕中心
   Begin VB.CommandButton cmdExit 
      Cancel          =   -1  'True
      Caption         =   "退　出"
      Height          =   495
      Left            =   2520
      TabIndex        =   4
      ToolTipText     =   "退出按钮"
      Top             =   2160
      Width           =   1215
   End
   Begin VB.CommandButton cmdOk 
      Caption         =   "确　定"
      Default         =   -1  'True
      Height          =   495
      Left            =   840
      TabIndex        =   3
      ToolTipText     =   "确定按钮"
      Top             =   2160
      Width           =   1215
   End
   Begin VB.TextBox txtUser 
      Height          =   375
      Left            =   1800
      TabIndex        =   1
      ToolTipText     =   "请输入用户名"
      Top             =   653
      Width           =   2055
   End
   Begin VB.TextBox txtPasswd 
      Height          =   375
      IMEMode         =   3  'DISABLE
      Left            =   1800
      PasswordChar    =   "*"
      TabIndex        =   2
      ToolTipText     =   "请输入密码"
      Top             =   1373
      Width           =   2055
   End
   Begin VB.Label lblUser 
      AutoSize        =   -1  'True
      Caption         =   "用户名："
      Height          =   180
      Left            =   840
      TabIndex        =   5
      Top             =   750
      Width           =   720
   End
   Begin VB.Label lblPasswd 
      AutoSize        =   -1  'True
      Caption         =   "密　码："
      Height          =   180
      Left            =   840
      TabIndex        =   0
      Top             =   1470
      Width           =   720
   End
End
Attribute VB_Name = "frmPasswd"
Attribute VB_GlobalNameSpace = False
Attribute VB_Creatable = False
Attribute VB_PredeclaredId = True
Attribute VB_Exposed = False
'定义重试次数
Public counter As Integer

'窗体装载事件
Private Sub Form_Load()
  '初始化重试次数
  counter = 0
End Sub

'单击确定按钮
Private Sub cmdOK_Click()
  '定义user变量，用于存储用户名
  Dim user As String
  '给user赋值
  user = Trim(txtUser.Text)
  '定义pwd变量，用于存储密码
  Dim pwd As String
  '给密码赋值
  pwd = Trim(txtPasswd.Text)
  
  '没有输入用户名
  If Trim(user) = "" Then
    MsgBox "请输入用户名", vbInformation, "信息提示"
    txtUser.SetFocus
    Exit Sub
  End If

  '判断用户是否存在
  If Not objPasswd.IsExistUser(user) Then
    counter = counter + 1
    If counter < 3 Then
      MsgBox "用户名不存在，请重新输入！", vbOKOnly + vbInformation, _
              "用户名错误"
      txtUser.Text = ""
      txtPasswd.Text = ""
      txtUser.SetFocus
      Exit Sub
    Else
      MsgBox "重试次数已到，不能再输入用户名和密码，即将退出系统！", _
              vbOKOnly + vbExclamation, "用户名错误"
      DBDisconnect
      End
      Exit Sub
    End If
  End If

  '判断密码是否正确
  objPasswd.GetInfo (user)
  If objPasswd.Passwd <> pwd Then
    counter = counter + 1
    If counter < 3 Then
      MsgBox "用户或密码错误，请重新输入！", vbOKOnly + vbInformation, _
              "密码错误"
      txtUser.Text = ""
      txtPasswd.Text = ""
      txtUser.SetFocus
      Exit Sub
    Else
      MsgBox "重试次数已到，不能再输入用户名和密码，即将退出系统！", _
            vbOKOnly + vbExclamation, "密码错误"
      DBDisconnect
      End
      Exit Sub
    End If
  End If
  
  '登录成功，将当前用户的信息保存在objCurPasswd中
  objCurPasswd.UserName = objPasswd.UserName
  objCurPasswd.UserType = objPasswd.UserType
  '关闭自己
  Unload Me
  frmMain.Show
 '当重新登录时用到
  frmMain.Enabled = True
End Sub

'单击退出按钮
Private Sub cmdExit_Click()
  DBDisconnect
  End
End Sub