Question

我已经创建了一个系统，并且是vb.net的新手。它工作正常。问题是，我需要限制主页面1.）用户和2.）管理员。

例如，登录后，管理员将进入主页面如果用户登录，他们将被定向到另一个页面

我还是vb.net的新手（比如6周前），我正在使用microsoft access作为我的数据库。我在网上找到的很多代码都是非常复杂和技术性的。我只需要简单的vb.net代码

任何帮助将不胜感激，谢谢！我已经为我的登录表单发布了我的代码，所以你们可以进一步理解我的编码：

Public Class Form1
    Dim loginerror As String
    Public Function login()
    Dim DBconn As New ADODB.Connection
    Dim user As New ADODB.Recordset

    Dim Username As String
    Dim userDB As String
    Dim passDB As String

    Dim UserFound As Boolean

    DBconn.Open("Provider = Microsoft.Jet.OLEDB.4.0;" & _
                "Data Source = '" & Application.StartupPath & "\LoginDB.mdb'")

    user.Open("UserTable", DBconn, ADODB.CursorTypeEnum.adOpenStatic, ADODB.LockTypeEnum.adLockOptimistic)

    UserFound = False
    login = False
    Username = "Username = '" & txtuser.Text & "'" '

    Do
        user.Find(Username)
        If user.BOF = False And user.EOF = False Then
            userDB = user.Fields("Username").Value.ToString

            passDB = user.Fields("Password").Value.ToString

            If userDB <> txtuser.Text Then
                user.MoveNext()
            Else
                UserFound = True
                If passDB = txtpass.Text Then
                    user.Close()
                    DBconn.Close()
                    Return True
                Else
                    loginerror = "Invalid Password"
                    user.Close()
                    DBconn.Close()
                    Return False
                End If
            End If
        Else
            loginerror = "Invalid Username"
            user.Close()
            DBconn.Close()
            Return False
        End If
    Loop Until UserFound = True
    user.Close()
    DBconn.Close()
    Return False


End Function


Private Sub Button1_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles Button1.Click
    If login() = True Then
        Welcome.Show()
        Me.Close()
    Else
        MessageBox.Show(loginerror, "Login Message")
    End If
End Sub


Private Sub Form1_Load(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles MyBase.Load
    AcceptButton = Button1
    Me.Show()
    Application.DoEvents()
    txtuser.Focus()
End Sub

Private Sub txtpass_TextChanged(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles txtpass.TextChanged

End Sub

Private Sub Label2_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles Label2.Click

End Sub

Private Sub txtuser_TextChanged(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles txtuser.TextChanged

End Sub

Private Sub Label1_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles Label1.Click

End Sub

Private Sub PictureBox1_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles PictureBox1.Click

End Sub

Private Sub Label3_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles Label3.Click

End Sub

End Class

以防这是我的主要表格的编码：

Public Class Mainform
Private Sub Form1_FormClosing(ByVal sender As Object, ByVal e As System.Windows.Forms.FormClosingEventArgs) Handles Me.FormClosing
    Select MessageBox.Show("Are you sure you want to exit?", "Confirm", MessageBoxButtons.YesNo, MessageBoxIcon.Question)
        Case Windows.Forms.DialogResult.Yes
        Case Windows.Forms.DialogResult.No
            e.Cancel = True
    End Select

End Sub

Private Sub Mainform_Load(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles MyBase.Load
    Me.WorkTableAdapter.Fill(Me.LoginDBDataSet.Work)

    Me.AssetTableAdapter.Fill(Me.LoginDBDataSet.Asset)

    Me.HistoryTableAdapter.Fill(Me.LoginDBDataSet.History)

    Me.InventoryTableAdapter.Fill(Me.LoginDBDataSet.Inventory)

    Me.Equipment1TableAdapter.Fill(Me.LoginDBDataSet.Equipment1)


End Sub
Private Sub mainform_KeyDown(ByVal sender As Object, ByVal e As System.Windows.Forms.KeyEventArgs) Handles MyBase.KeyDown
    If e.KeyCode = Keys.Escape Then Me.Close()

End Sub

Private Sub Equipment1BindingNavigatorSaveItem_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles Equipment1BindingNavigatorSaveItem.Click
    Me.Validate()
    Me.Equipment1BindingSource.EndEdit()
    Me.TableAdapterManager.UpdateAll(Me.LoginDBDataSet)

End Sub

Private Sub ToolStripButton1_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles ToolStripButton1.Click
    Mainform_Load(Me, New System.EventArgs)
End Sub

Private Sub ToolStripButton2_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles ToolStripButton2.Click
    Form1.Show()
    Me.Dispose()
    Me.Close()

End Sub

Private Sub TabPage1_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles TabPage1.Click

End Sub

Private Sub IDLabel_Click(ByVal sender As System.Object, ByVal e As System.EventArgs)

End Sub

Private Sub TabPage5_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles TabPage5.Click

End Sub

Private Sub Equipment_NameTextBox_TextChanged(ByVal sender As System.Object, ByVal e As System.EventArgs)

End Sub

Private Sub HistoryDataGridView_CellContentClick(ByVal sender As System.Object, ByVal e As System.Windows.Forms.DataGridViewCellEventArgs)

End Sub

Private Sub InventoryDataGridView_CellContentClick(ByVal sender As System.Object, ByVal e As System.Windows.Forms.DataGridViewCellEventArgs)

End Sub

Private Sub TabControl1_SelectedIndexChanged(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles TabControl1.SelectedIndexChanged

End Sub

Private Sub Machine_IDTextBox_TextChanged(ByVal sender As System.Object, ByVal e As System.EventArgs)

End Sub

Private Sub _WO_CompletedLabel_Click(ByVal sender As System.Object, ByVal e As System.EventArgs)

End Sub

Private Sub _WO_CompletedCheckBox_CheckedChanged(ByVal sender As System.Object, ByVal e As System.EventArgs)

End Sub

Private Sub _WO_CompletedCheckBox_CheckedChanged_1(ByVal sender As System.Object, ByVal e As System.EventArgs)

End Sub

Private Sub Machine_IDTextBox1_TextChanged(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles Machine_IDTextBox1.TextChanged

End Sub

Private Sub _WO_CompletedCheckBox_CheckedChanged_2(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles _WO_CompletedCheckBox.CheckedChanged

End Sub
End Class

Answer 1

您需要确定用户是否是管理员（通常您的用户表应该具有附加到用户的角色，例如管理员工，员工等）。

当您尝试登录

时，会出现类似的情况

Private Sub Button1_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles Button1.Click
If login() = True and UserRole='Administrator' Then
    Welcome.Show()
    Me.Close()
elseif login() = True then
    WelcomeUser.Show()
    Me.Close()
Else
    MessageBox.Show(loginerror, "Login Message")
End If

End Sub

VB.NET上的访问级别

1 个答案: