help on redirect to the last page update in database

Question

User1325920427 posted

Hi,

I really need help on to redirect page:

1) if the last page in database is null ---> the redirect page will automatically appoint user to the first page

2) if if the last page in database is page 3 ---> the redirect page will automatically appoint user to the third page

i already run the code, i still can get the right result, when i debug, i found 

whenever i write

If strLastPAGE = "" Then

--> this will redirect page to the last page update in database

but when i change the code

  If strLastPAGE = "0" Then

--> this will redirect page to the first page whitout taking the value last page update in database

here i place the code so far:

  Private Sub btnLogin_Click(ByVal sender As Object, ByVal e As System.EventArgs) Handles btnLogin.Click

        strSQL = "SELECT LoginID FROM UserMark WHERE LoginID='" & oCommon.FixSingleQuotes(txtEmail.Text) & "' AND Pwd='" & oCommon.FixSingleQuotes(txtPassword.Text) & "'"
        If oCommon.isExist(strSQL) = True Then

            Response.Cookies("islogin").Value = "Y"

            ''get userid and surveyid

            strSQL = "SELECT UserID FROM UserMark WHERE LoginID='" & oCommon.FixSingleQuotes(txtEmail.Text) & "'"
            strUserID = oCommon.getFieldValue(strSQL)

            strSQL = "SELECT SurveyID FROM UserMark WHERE LoginID='" & oCommon.FixSingleQuotes(txtEmail.Text) & "'"
            strSurveyID = oCommon.getFieldValue(strSQL)

        Else
            Response.Cookies("islogin").Value = "N"
            lblLoginMsg.Text = "Invalid Login ID or Password. Please try again."
        End If

        '' validate last page update
        Try
            If validateLastPage() = False Then
                Exit Sub
            End If

        Catch ex As Exception

        End Try

    End Sub

    Private Function validateLastPage() As Boolean

        Dim strNextpage As String = "esurvey.default.aspx?userid=" & strUserID & "&surveyid=" & strSurveyID & "&culture=en-US&" & Request.QueryString("culture")

        strSQL = "SELECT LastPage FROM UserMark WHERE LoginID='" & strUserID & "'"
        strLastPAGE = oCommon.ExecuteSQL(strSQL)

        If strLastPAGE = "" Then
            Response.Redirect(strNextpage)
            Return False
        Else
            strSQL = "SELECT LastPage FROM UserMark WHERE UserID='" & strUserID & "'"
            strLastPAGE = oCommon.getFieldValue(strSQL)
            Dim notCompletePage As String = strLastPAGE & "?userid=" & strUserID & "&surveyid=" & strSurveyID & "&culture=en-US&" & Request.QueryString("culture")
            Response.Redirect(notCompletePage)
            Return False
        End If

        Return True

    End Function

really need help on urgently . thank you so much

 

Answer 1

User1320101480 posted

Check for Null values using IsNull

Answer 2

User1325920427 posted

hi, thanks for the reply, i change the code

If String.IsNullOrEmpty(strLastPAGE) Then
            Response.Redirect(strNextpage)

and the whole code:

Private Function validateLastPage() As Boolean

        Dim strNextpage As String = "esurvey.default.aspx?userid=" & strUserID & "&surveyid=" & strSurveyID & "&culture=en-US&" & Request.QueryString("culture")

        strSQL = "SELECT LastPage FROM UserMark WHERE LoginID='" & strUserID & "'"
        strLastPAGE = oCommon.ExecuteSQL(strSQL)

        If String.IsNullOrEmpty(strLastPAGE) Then
            Response.Redirect(strNextpage)
            Return False
        Else
            strSQL = "SELECT LastPage FROM UserMark WHERE UserID='" & strUserID & "'"
            strLastPAGE = oCommon.getFieldValue(strSQL)
            Dim notCompletePage As String = strLastPAGE & "?userid=" & strUserID & "&surveyid=" & strSurveyID & "&culture=en-US&" & Request.QueryString("culture")
            Response.Redirect(notCompletePage)
            Return False
        End If

        Return True

    End Function

still not work

Answer 3

User1046077057 posted

Hi,

What do you mean of doesn't work? If you want to check whether it can redirect to the strNextpage you can check the value of the strLastPage. You can check whether the strLastPAGE is null or empty. If it is not null or empty you need to modify the sqlcommand.