usersmanager.vb

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Imports Microsoft.VisualBasic
Imports System.Data
Imports System.Data.SqlClient
Public Class UsersManager
    Dim connString As String = "server=localhost\sqlexpress;integrated security=sspi;database=GDMS"
    Dim cn As New SqlConnection(connString)
    Dim cmd As New SqlCommand
    Dim cmdText As String
    Dim dr As SqlDataReader

    Public Function srd() As SqlDataReader
        cn.Open()
        cmd.Connection = cn
        cmdText = "select * from users where userid='0427128'"
        cmd.CommandText = cmdText
        dr = cmd.ExecuteReader()

        dr.Read()

        Return dr
        cn.Close()
    End Function
    Public Function ActivateUser(ByVal userID As String, ByVal password As String, ByVal email As String, ByVal passwordQuestion As String, ByVal passwordAnswer As String) As Boolean

        cn.Open()

        cmd.Connection = cn
        cmdText = "update Users set password='" + password + "',email='" + email + "',question='" + passwordQuestion + "',answer='" + passwordAnswer + "',state='true'" _
        + " where userid='" + userID + "'"
        cmd.CommandText = cmdText
        cmd.ExecuteNonQuery()

        cn.Close()
        Return True
    End Function
    Public Function ChangePassword(ByVal userID As String, ByVal oldPassword As String, ByVal newPassword As String) As Boolean
        cn.Open()
        cmd.Connection = cn
        cmdText = "update Users set password='" + newPassword + "' where (userid='" + userID + "') and (password='" + oldPassword + "')"
        Try
            cmd.ExecuteNonQuery()
            Return True
        Catch ex As Exception
            Return False
        Finally
            cn.Close()
        End Try
    End Function
    Public Function Login(ByVal userID As String, ByVal password As String) As String
        Dim username As String = "?"
        cn.Open()
        cmd.Connection = cn
        cmdText = "select username from Users where (userid='" + userID + "') and (password='" + password + "')"
        cmd.CommandText = cmdText
        dr = cmd.ExecuteReader()

        If dr.Read() Then
            username = dr("username")
        End If

        cn.Close()
        Return username
    End Function
    Public Function Login(ByVal userID As String, ByVal password As String, ByRef username As String, ByRef role As String) As Boolean
        Dim dr As SqlDataReader

        cn.Open()
        cmd.Connection = cn
        cmdText = "select * from Users where (userid='" + userID + "') and (password='" + password + "')"
        cmd.CommandText = cmdText
        dr = cmd.ExecuteReader()

        'If dr.Read() Then
        '    username = dr("username")
        'End If
        Try
            dr.Read()
            username = dr("username")
            role = dr("role")
            Return True
        Catch ex As Exception

            Return False
        Finally
            cn.Close()
        End Try
    End Function
    Public Function GetPasswordbyAnswer(ByVal userID As String, ByVal answer As String) As String
        Dim password As String
        password = "?"
        cn.Open()
        cmd.Connection = cn
        cmdText = "select password from Users where (userid='" + userID + "') and (answer='" + answer + "')"

        dr = cmd.ExecuteReader()

        If dr.Read() Then
            password = dr("password")
        End If


        Return password
    End Function

    Public Function GetPasswordbyEmail(ByVal userID As String, ByVal email As String) As String
        Dim password As String
        password = ""
        Return password
    End Function
    Public Function UserExists(ByVal userID As String) As Integer
        cn.Open()
        cmd.Connection = cn
        cmdText = "select userid from Users where userid='" + userID + "'"
        cmd.CommandText = cmdText
        dr = cmd.ExecuteReader()
        If Not dr.Read() Then '未注册
            UserExists = 0
        ElseIf dr("state") = True Then '用户已经注册
            UserExists = 1
        Else '用户未激活
            UserExists = 2
        End If
        cn.Close()
    End Function
End Class