'UserRole'未声明。('UserRole' is not declared. It may be inaccessible due to its protection level)

 我使用VB.NET和microsoft访问作为我的数据库，我是VB.NET的新手，我试图根据当前角色制作不同的访问级别。例如，登录后，Admin将进入主页面。用户登录后，会将其定向到其他页面。 我已经在我的数据库中设置了不同的角色，我在网上发现了一些编码来帮助我 
 
 但是我继续收到错误'UserRole'没有声明。 由于其保护级别，它可能无法访问。 我需要先声明UserRole吗？ 如果是的话，我该怎么做？ 任何帮助将不胜感激，谢谢:) 
 
 公共类Form1 Dim loginerror As String Dim UserRole As String公共函数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
                    UserRole = user.Fields("roles").Value.ToString
                    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 And UserRole = "admin" Then
        adminwelcome.Show()
        Me.Close()
    ElseIf 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
 
 结束类 

I am using VB.NET and microsoft access as my database, i am new to VB.NET and i tried to make different access levels depending on the current role.For example, After logging in, Admin will proceed to the main page And if users logs in, they will be directed to a different page. I have already set the different roles in my database, and i found some coding online to help me
 
However i keep getting the error 'UserRole' is not declared. It may be inaccessible due to its protection level. Do i need to declare UserRole first? if so, how do i do it? Any help would be much appreciated , thank you :)
 
Public Class Form1 Dim loginerror As String Dim UserRole 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
                    UserRole = user.Fields("roles").Value.ToString
                    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 And UserRole = "admin" Then
        adminwelcome.Show()
        Me.Close()
    ElseIf 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

原文：https://stackoverflow.com/questions/17666765