frmlogin.frm

VB+access学生信息管理系统,基本完成了学生信息的添加,修改,打印,查询功能.大家互相学习吧.

VERSION 5.00
Begin VB.Form frmLogin 
   BorderStyle     =   3  'Fixed Dialog
   Caption         =   "用户登录"
   ClientHeight    =   3150
   ClientLeft      =   3555
   ClientTop       =   3840
   ClientWidth     =   5565
   ControlBox      =   0   'False
   LinkTopic       =   "Form1"
   LockControls    =   -1  'True
   MaxButton       =   0   'False
   MinButton       =   0   'False
   ScaleHeight     =   3150
   ScaleMode       =   0  'User
   ScaleWidth      =   5565
   ShowInTaskbar   =   0   'False
   Begin VB.TextBox txtUserName 
      Height          =   345
      Left            =   2250
      TabIndex        =   1
      Top             =   975
      Width           =   2325
   End
   Begin VB.CommandButton cmdOK 
      Caption         =   "确定"
      Height          =   330
      Left            =   1515
      TabIndex        =   4
      Top             =   2160
      Width           =   1020
   End
   Begin VB.CommandButton cmdCancel 
      Cancel          =   -1  'True
      Caption         =   "取消"
      Height          =   330
      Left            =   3120
      TabIndex        =   5
      Top             =   2160
      Width           =   1020
   End
   Begin VB.TextBox txtPassword 
      Height          =   345
      IMEMode         =   3  'DISABLE
      Left            =   2250
      PasswordChar    =   "*"
      TabIndex        =   3
      Top             =   1485
      Width           =   2325
   End
   Begin VB.Label Label2 
      Caption         =   "Visual Basic编程及实例分析教程综合实例 开发者:郑海春 2006年"
      ForeColor       =   &H00008000&
      Height          =   255
      Left            =   120
      TabIndex        =   7
      Top             =   2820
      Width           =   5355
   End
   Begin VB.Line Line1 
      BorderColor     =   &H00808080&
      X1              =   120
      X2              =   5385
      Y1              =   2700
      Y2              =   2700
   End
   Begin VB.Label Label1 
      Alignment       =   2  'Center
      Caption         =   "学生信息管理系统"
      BeginProperty Font 
         Name            =   "楷体_GB2312"
         Size            =   18
         Charset         =   134
         Weight          =   400
         Underline       =   0   'False
         Italic          =   0   'False
         Strikethrough   =   0   'False
      EndProperty
      ForeColor       =   &H00C00000&
      Height          =   495
      Left            =   420
      TabIndex        =   6
      Top             =   240
      Width           =   4755
   End
   Begin VB.Label lblLabels 
      Caption         =   "用户名(&U):"
      Height          =   270
      Index           =   0
      Left            =   1065
      TabIndex        =   0
      Top             =   990
      Width           =   1080
   End
   Begin VB.Label lblLabels 
      Caption         =   "密  码(&P):"
      Height          =   270
      Index           =   1
      Left            =   1065
      TabIndex        =   2
      Top             =   1500
      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

Dim try_times As Integer '尝试登陆次数

Private Sub Form_Load()
    '设置数据库路径
    StudentDBfile = App.Path & "\StudentMIS.mdb"
    '窗体中心定位
    Call ScreenCenter(Me)
End Sub

Private Sub cmdCancel_Click()
    '结束应用程序
    If MsgBox("你选择了退出登陆，是否退出?", _
       vbYesNo + vbInformation, "用户登陆") = vbYes Then
        End
    Else
        Exit Sub
    End If
End Sub

Private Sub cmdOK_Click()
Dim sName As String, sPas As String
Dim mrs As ADODB.Recordset, strSQL As String
    sName = Trim(txtUserName.Text): sPas = Trim(txtPassword.Text)
    '数据有效性检查
    If sName = "" Then
        MsgBox "请输入用户名!", vbCritical, "用户登陆验证"
        txtUserName.SetFocus
        Exit Sub
    End If
    If sPas = "" Then
        MsgBox "请输入密码!", vbCritical, "用户登陆验证"
        txtPassword.SetFocus
        Exit Sub
    End If
    '检查用户名是否正确
    strSQL = "select * from login where user='" & sName & "'"
    Set mrs = ExecuteSQL(strSQL)
    If mrs.EOF = True Then
        MsgBox "用户名不存在！", vbCritical, "用户登陆验证"
        try_times = try_times + 1
        If try_times >= 3 Then
            MsgBox "您已经三次尝试进入本系统，均不成功，系统将关闭！", _
                   vbCritical, "用户登陆验证"
            End
        Else
            txtUserName.SetFocus
            txtUserName.SelStart = 0
            txtUserName.SelLength = Len(txtUserName.Text)
            Exit Sub
        End If
    End If
    strSQL = "select * from login where user='" & sName & "'" & _
             "and password='" & sPas & "'"
    Set mrs = ExecuteSQL(strSQL)
    If mrs.EOF = True Then
        MsgBox " 密码错误！", vbCritical, "用户登陆验证"
        try_times = try_times + 1
        If try_times >= 3 Then
            MsgBox "您已经三次尝试进入本系统，均不成功，系统将关闭！", _
            vbCritical, "用户登陆验证"
            End
        Else
            txtPassword.SetFocus
            txtPassword.SelStart = 0
            txtPassword.SelLength = Len(txtPassword.Text)
            Exit Sub
        End If
    End If
    MsgBox "登陆成功！", vbInformation, "用户登陆验证"
    '保存当前登陆的权限
    bolAuthority = mrs.Fields("admin")
    '加载MDI主窗体
    StudentMIS.Show
    '卸载登陆窗体
    Unload Me
End Sub

Private Sub txtUserName_KeyPress(KeyAscii As Integer)
    '用于在输入完用户名后并按回车键后跳到输入密码文本框
    If KeyAscii = 13 Then txtPassword.SetFocus
End Sub

Private Sub txtPassword_KeyPress(KeyAscii As Integer)
    '用于在输入完密码后并按回车键后跳到确定命令按钮
    If KeyAscii = 13 Then cmdOK.SetFocus
End Sub