formlogin.frm

来自「vb数据库编程资料」· FRM 代码 · 共 172 行

VERSION 5.00
Begin VB.Form frmLogin 
   BorderStyle     =   3  'Fixed Dialog
   Caption         =   "登录"
   ClientHeight    =   2880
   ClientLeft      =   2835
   ClientTop       =   3480
   ClientWidth     =   4590
   LinkTopic       =   "Form1"
   MaxButton       =   0   'False
   MinButton       =   0   'False
   ScaleHeight     =   1701.598
   ScaleMode       =   0  'User
   ScaleWidth      =   4309.761
   ShowInTaskbar   =   0   'False
   StartUpPosition =   2  '屏幕中心
   Begin VB.TextBox txtUserName 
      Height          =   345
      Left            =   1650
      MaxLength       =   10
      TabIndex        =   1
      Text            =   "Admin"
      Top             =   840
      Width           =   2325
   End
   Begin VB.CommandButton cmdOK 
      Caption         =   "登录(&L)"
      Default         =   -1  'True
      Height          =   390
      Left            =   855
      TabIndex        =   4
      Top             =   1725
      Width           =   1140
   End
   Begin VB.CommandButton cmdCancel 
      Cancel          =   -1  'True
      Caption         =   "退出(&E)"
      Height          =   390
      Left            =   2640
      TabIndex        =   5
      Top             =   1725
      Width           =   1140
   End
   Begin VB.TextBox txtPassword 
      Height          =   345
      IMEMode         =   3  'DISABLE
      Left            =   1650
      MaxLength       =   10
      PasswordChar    =   "*"
      TabIndex        =   3
      Text            =   "Admin"
      Top             =   1230
      Width           =   2325
   End
   Begin VB.Label Label2 
      Caption         =   "版权所有 2003  清华大学出版社"
      BeginProperty Font 
         Name            =   "宋体"
         Size            =   14.25
         Charset         =   134
         Weight          =   400
         Underline       =   0   'False
         Italic          =   0   'False
         Strikethrough   =   0   'False
      EndProperty
      Height          =   255
      Left            =   240
      TabIndex        =   7
      Top             =   2400
      Width           =   4335
   End
   Begin VB.Label Label1 
      Caption         =   "教学信息管理系统"
      BeginProperty Font 
         Name            =   "华文新魏"
         Size            =   21.75
         Charset         =   134
         Weight          =   400
         Underline       =   0   'False
         Italic          =   0   'False
         Strikethrough   =   0   'False
      EndProperty
      Height          =   495
      Left            =   1080
      TabIndex        =   6
      Top             =   120
      Width           =   2655
   End
   Begin VB.Label lblLabels 
      Caption         =   "用户编号(&U):"
      Height          =   270
      Index           =   0
      Left            =   480
      TabIndex        =   0
      Top             =   855
      Width           =   1080
   End
   Begin VB.Label lblLabels 
      Caption         =   "密　　码(&P):"
      Height          =   270
      Index           =   1
      Left            =   465
      TabIndex        =   2
      Top             =   1245
      Width           =   1080
   End
End
Attribute VB_Name = "frmLogin"
Attribute VB_GlobalNameSpace = False
Attribute VB_Creatable = False
Attribute VB_PredeclaredId = True
Attribute VB_Exposed = False
Option Explicit

Public LoginSucceeded As Boolean

Private Sub cmdCancel_Click()
  End
End Sub

Private Sub cmdOK_Click()
  Dim Conn As ADODB.Connection
  Dim rs As ADODB.Recordset
  Dim strUserID As String
  Dim strPassword As String
  Dim strSQL As String
  Static Count As Byte
  
  strUserID = Replace(Trim(txtUserName.Text), "'", "")
  strPassword = Replace(Trim(txtPassword.Text), "'", "")
  
  If strUserID = "" Then
    MsgBox "用户名不能为空，请输入用户名！", , "登录错误"
    txtUserName.SetFocus
    Exit Sub
  ElseIf strPassword = "" Then
    MsgBox "密码不能为空，请输入密码！", , "登录错误"
    txtPassword.SetFocus
    Exit Sub
  End If
  
  Set Conn = New ADODB.Connection
  Set rs = New ADODB.Recordset
  strSQL = "SELECT * FROM USERS WHERE UserID='" & strUserID & "' "
  strSQL = strSQL & " AND Password = '" & strPassword & "';"
  
  Conn.Open ConnString
  rs.Open strSQL, Conn
  If rs.EOF Then
    Count = Count + 1
    MsgBox "用户名不存在或密码错误!", , "登录失败"
    txtUserName.Text = ""
    txtPassword.Text = ""
    txtUserName.SetFocus
  Else
    LoginSucceeded = True
    UserID = strUserID
    UserName = rs("UserName").Value
    Me.Hide
  End If
  rs.Close
  Conn.Close
  Set rs = Nothing
  Set Conn = Nothing
  
  If Count >= 3 Then
    MsgBox "超过登录次数，无权登录本系统！", , "登录失败"
    End
  End If
End Sub