一个Cookies的问题

Question

为什么点击按钮后总是提示 "您已经投完票了",程序有什么地方错误吗???
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Private Sub Page_Load(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles MyBase.Load
        '在此处放置初始化页的用户代码
        Response.Cookies("user_IP").Expires = DateTime.Now.AddMinutes(1)
     
    End Sub    Private Sub Button1_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles Button1.Click
        Dim MyCookie As HttpCookie = Request.Cookies("user_IP")
        If MyCookie Is Nothing Or MyCookie.ToString = "" Then
            Response.Write("<script language=javascript>alert('感谢您的投票！');</script>")
            Dim user_IP As String
            If Not (Request.ServerVariables("HTTP_VIA") Is Nothing) Then
                user_IP = Request.ServerVariables("HTTP_X_FORWARDED_FOR").ToString
            Else
                user_IP = Request.ServerVariables("REMOTE_ADDR").ToString
            End If
            Response.Cookies("user_IP").Value = user_IP        Else
            Response.Write("<script language=javascript>alert('您已经投完票了！');</script>")
        End If
    End Sub

Answer 1

If MyCookie Is Nothing Or MyCookie.ToString = "" Then
 ---------------------------->
If not (MyCookie Is Nothing Or MyCookie.ToString = "") Then

Answer 2

pageload内那句想要做什么呀？

Answer 3

我修改成这样,为什么还是不对呀????
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    Private Sub Button1_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles Button1.Click
        Dim MyCookie As HttpCookie = New HttpCookie("LastVisit")
        If MyCookie Is Nothing Or MyCookie.ToString = "" Then
            Response.Write("<script language=javascript>alert('感谢您的投票！');</script>")
            Dim user_IP As String
            If Not (Request.ServerVariables("HTTP_VIA") Is Nothing) Then
                user_IP = Request.ServerVariables("HTTP_X_FORWARDED_FOR").ToString
            Else
                user_IP = Request.ServerVariables("REMOTE_ADDR").ToString
            End If
            Response.Cookies("user_IP").Value = user_IP
            MyCookie.Value = user_IP
            MyCookie.Expires = DateTime.Now.AddMinutes(10)
            Response.Cookies.Add(MyCookie)
            Dim connection As String = ConfigurationSettings.AppSettings("ST2003") '僨乕僞儀乕僗僾儘僷僥傿偺掕媊
            Dim myconnection As New SqlConnection(connection)
            myconnection.Open()
            Dim insertstring As String = "insert into TTemporaryinvestigate (subject1,subject2,subject3,subject4,subject5,subject6,subject7,subject8,subject9,subject10,subject11,subject12,subject13,subject14,subject15,subject16,subject5D,subject11D)VALUES('" & Request.Form("radiobutton1") & "','" & Request.Form("radiobutton2") & "','" & Request.Form("radiobutton3") & "','" & Request.Form("radiobutton4") & "','" & Request.Form("checkbox1") & "','" & Request.Form("checkbox2") & "','" & Request.Form("checkbox3") & "','" & Request.Form("radiobutton5") & "','" & Request.Form("radiobutton6") & "','" & Request.Form("radiobutton7") & "','" & Request.Form("checkbox4") & "','" & Request.Form("textarea1") & "','" & Request.Form("textarea2") & "','" & Request.Form("radiobutton8") & "','" & Request.Form("radiobutton9") & "','" & Request.Form("d15") & "','" & Request.Form("textfield1") & "','" & Request.Form("textfield2") & "')"
            Dim mycommand As New SqlCommand(insertstring, myconnection)
            mycommand.ExecuteNonQuery()        Else
            Response.Write("<script language=javascript>alert('您已经投完票了！');</script>")
        End If
    End Sub

Answer 4

你的cookie是否正确写入了？