frmmain.vb

vb.net+SQL开发工具 是一个很好的管理系统的源码

Public Class frmMain
    Inherits System.Windows.Forms.Form

#Region " Windows 窗体设计器生成的代码 "

    Public Sub New()
        MyBase.New()

        '该调用是 Windows 窗体设计器所必需的。
        InitializeComponent()

        '在 InitializeComponent() 调用之后添加任何初始化

    End Sub

    '窗体重写 dispose 以清理组件列表。
    Protected Overloads Overrides Sub Dispose(ByVal disposing As Boolean)
        If disposing Then
            If Not (components Is Nothing) Then
                components.Dispose()
            End If
        End If
        MyBase.Dispose(disposing)
    End Sub

    'Windows 窗体设计器所必需的
    Private components As System.ComponentModel.IContainer

    '注意: 以下过程是 Windows 窗体设计器所必需的
    '可以使用 Windows 窗体设计器修改此过程。
    '不要使用代码编辑器修改它。
    Friend WithEvents MainMenu1 As System.Windows.Forms.MainMenu
    Friend WithEvents mnBasic As System.Windows.Forms.MenuItem
    Friend WithEvents mnClass As System.Windows.Forms.MenuItem
    Friend WithEvents mnStudent As System.Windows.Forms.MenuItem
    Friend WithEvents mnSubject As System.Windows.Forms.MenuItem
    Friend WithEvents mnTeach As System.Windows.Forms.MenuItem
    Friend WithEvents mnSelect As System.Windows.Forms.MenuItem
    Friend WithEvents mnCourse As System.Windows.Forms.MenuItem
    Friend WithEvents mnResult As System.Windows.Forms.MenuItem
    Friend WithEvents mnPrint As System.Windows.Forms.MenuItem
    Friend WithEvents mnExit As System.Windows.Forms.MenuItem
    Friend WithEvents mnReport As System.Windows.Forms.MenuItem
    <System.Diagnostics.DebuggerStepThrough()> Private Sub InitializeComponent()
        Dim resources As System.Resources.ResourceManager = New System.Resources.ResourceManager(GetType(frmMain))
        Me.MainMenu1 = New System.Windows.Forms.MainMenu
        Me.mnBasic = New System.Windows.Forms.MenuItem
        Me.mnClass = New System.Windows.Forms.MenuItem
        Me.mnStudent = New System.Windows.Forms.MenuItem
        Me.mnSubject = New System.Windows.Forms.MenuItem
        Me.mnTeach = New System.Windows.Forms.MenuItem
        Me.mnSelect = New System.Windows.Forms.MenuItem
        Me.mnCourse = New System.Windows.Forms.MenuItem
        Me.mnResult = New System.Windows.Forms.MenuItem
        Me.mnPrint = New System.Windows.Forms.MenuItem
        Me.mnReport = New System.Windows.Forms.MenuItem
        Me.mnExit = New System.Windows.Forms.MenuItem
        '
        'MainMenu1
        '
        Me.MainMenu1.MenuItems.AddRange(New System.Windows.Forms.MenuItem() {Me.mnBasic, Me.mnTeach, Me.mnPrint, Me.mnExit})
        '
        'mnBasic
        '
        Me.mnBasic.Index = 0
        Me.mnBasic.MenuItems.AddRange(New System.Windows.Forms.MenuItem() {Me.mnClass, Me.mnStudent, Me.mnSubject})
        Me.mnBasic.Text = "基础维护(&W)"
        '
        'mnClass
        '
        Me.mnClass.Index = 0
        Me.mnClass.Text = "班级信息维护(&X)"
        '
        'mnStudent
        '
        Me.mnStudent.Index = 1
        Me.mnStudent.Text = "学生信息维护(&Y)"
        '
        'mnSubject
        '
        Me.mnSubject.Index = 2
        Me.mnSubject.Text = "课程信息维护(&Z)"
        '
        'mnTeach
        '
        Me.mnTeach.Index = 1
        Me.mnTeach.MenuItems.AddRange(New System.Windows.Forms.MenuItem() {Me.mnSelect, Me.mnCourse, Me.mnResult})
        Me.mnTeach.Text = "教学管理(&X)"
        '
        'mnSelect
        '
        Me.mnSelect.Index = 0
        Me.mnSelect.Text = "学生选课(&X)"
        '
        'mnCourse
        '
        Me.mnCourse.Index = 1
        Me.mnCourse.Text = "课表查询(&Y)"
        '
        'mnResult
        '
        Me.mnResult.Index = 2
        Me.mnResult.Text = "成绩输入(&Z)"
        '
        'mnPrint
        '
        Me.mnPrint.Index = 2
        Me.mnPrint.MenuItems.AddRange(New System.Windows.Forms.MenuItem() {Me.mnReport})
        Me.mnPrint.Text = "报表统计(&Y)"
        '
        'mnReport
        '
        Me.mnReport.Index = 0
        Me.mnReport.Text = "打印成绩单(&Z)"
        '
        'mnExit
        '
        Me.mnExit.Index = 3
        Me.mnExit.Text = "退出系统(&Z)"
        '
        'frmMain
        '
        Me.AutoScaleBaseSize = New System.Drawing.Size(6, 14)
        Me.ClientSize = New System.Drawing.Size(416, 235)
        Me.Icon = CType(resources.GetObject("$this.Icon"), System.Drawing.Icon)
        Me.IsMdiContainer = True
        Me.Menu = Me.MainMenu1
        Me.Name = "frmMain"
        Me.Text = "EIS教务管理系统"

    End Sub

#End Region
    Private Function GetInstanceState(ByVal name As String) As Boolean
        '获得frmMain窗体的子窗体的数量
        Dim i As Integer = Me.MdiChildren.Length
        '循环判断是否有名为name的子窗体实例
        For i = 0 To Me.MdiChildren.Length - 1
            If Me.MdiChildren(i).Name = name Then
                '存在名为name的子窗体，是子窗体获得焦点并返回True
                Me.MdiChildren(i).Focus()
                Return True
            End If
        Next
        '不存在名为Name的子窗体False
        Return False
    End Function
    Private Sub mnClass_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles mnClass.Click
        If GetInstanceState("frmClass") Then
            Exit Sub
        End If
        Dim childFrm As frmClass = New frmClass
        childFrm.MdiParent = Me
        childFrm.Show()
    End Sub

    Private Sub mnStudent_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles mnStudent.Click
        If GetInstanceState("frmStudent") Then
            Exit Sub
        End If
        Dim childFrm As frmStudent = New frmStudent
        childFrm.MdiParent = Me
        childFrm.Show()
    End Sub

    Private Sub mnSubject_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles mnSubject.Click
        If GetInstanceState("frmSubject") Then
            Exit Sub
        End If
        Dim childFrm As frmSubject = New frmSubject
        childFrm.MdiParent = Me
        childFrm.Show()
    End Sub

    Private Sub mnSelect_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles mnSelect.Click
        If GetInstanceState("frmSelect") Then
            Exit Sub
        End If
        Dim childFrm As frmSelect = New frmSelect
        childFrm.MdiParent = Me
        childFrm.Show()
    End Sub

    Private Sub mnCourse_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles mnCourse.Click
        If GetInstanceState("frmCourse") Then
            Exit Sub
        End If
        Dim childFrm As frmCourse = New frmCourse
        childFrm.MdiParent = Me
        childFrm.Show()
    End Sub

    Private Sub mnResult_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles mnResult.Click
        If GetInstanceState("frmScore") Then
            Exit Sub
        End If
        Dim childFrm As frmScore = New frmScore
        childFrm.MdiParent = Me
        childFrm.Show()
    End Sub

    Private Sub mnReport_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles mnReport.Click
        If GetInstanceState("frmReport") Then
            Exit Sub
        End If
        Dim childFrm As frmReport = New frmReport
        childFrm.MdiParent = Me
        childFrm.Show()
    End Sub

    Private Sub mnExit_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles mnExit.Click

    End Sub
End Class