如何检查字符串是否在Visual Basic中的数组中？如何为每个函数编写return语句？

Question

Module Main
Friend blnLoggedIn As Boolean
Dim arrUsernames() As String = {"Admin, Clerk, Manager"}
Dim arrPasswords() As String = {"P@ssword, pa$$word, and passw0rd"}

Sub Login(username As String, password As String)
    blnLoggedIn = False
    If VerifyUsername(username) And VerifyPassword(password) Then
        'Find index for username
        Dim userIndex As Integer
        For loopIndex = 0 To arrUsernames.Length - 1
            If arrUsernames(loopIndex) = username Then
                userIndex = loopIndex
                Exit For
            End If
        Next
        'Check for password match
        If arrPasswords(userIndex) = password Then
            blnLoggedIn = True
        Else
            MessageBox.Show(“Incorrect password.”)
        End If
    End If

End Sub
Function VerifyUsername(username As String) As Boolean

    'If the username is found, Return True, otherwise Return False
End Function
Function VerifyPassword(password As String) As Boolean

    'If the passwords match, Return True, otherwise Return False
End Function

End Module

我的指示说：

使用您对搜索数组的了解，实现VerifyUsername和VerifyPassword函数。如果在arrUsernames或arrPasswords数组中分别找到用户名或密码，则它们应该返回true。