Postback & Click Event Issues - Help Please

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October 4th, 2005, 10:22 PM

JeremyCade

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Join Date: Oct 2005

Location: Brisbane/Austrlaia

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Postback & Click Event Issues - Help Please

Hi Everyone,

I'm new to .net and i'm having a problem with a postback event..

What I have is a group of drop down boxes, two of which are populated with dates during pageload, one is a hard coded country list, the last is a list of city's in a particular country, which is populated from the country selected value of the coutry list. The country list has AutoPostBack set as true.

My problem is that once i complete a postback, ie Change country to get a different city list, The click event for my button doesnt work..

I was wondering if someone could read over the code below and see if they can pick any logic issues?

Help is much appreciated...

---------------------------------------------------------------------------

Code:

Original - Code

Imports System.Data.SqlClient

Public Class LocPage
    Inherits System.Web.UI.Page

#Region " Web Form Designer Generated Code "

'This call is required by the Web Form Designer.
    Protected WithEvents rptResults As System.Web.UI.WebControls.Repeater
    Protected WithEvents litCityID As System.Web.UI.WebControls.Literal
    Protected WithEvents litTime As System.Web.UI.WebControls.Literal
    Protected WithEvents litMsg As System.Web.UI.WebControls.Literal
    Protected WithEvents ddlLMIn As System.Web.UI.WebControls.DropDownList
    Protected WithEvents ddlLMOut As System.Web.UI.WebControls.DropDownList
    Protected WithEvents ddlLMCtry As System.Web.UI.WebControls.DropDownList
    Protected WithEvents ddlLMCity As System.Web.UI.WebControls.DropDownList
    Protected WithEvents btnSearch As System.Web.UI.WebControls.Button

<System.Diagnostics.DebuggerStepThrough()> Private Sub InitializeComponent()

End Sub

'NOTE: The following placeholder declaration is required by the Web Form Designer.
    'Do not delete or move it.
    Private designerPlaceholderDeclaration As System.Object

Private Sub Page_Init(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles MyBase.Init
        'CODEGEN: This method call is required by the Web Form Designer
        'Do not modify it using the code editor.
        InitializeComponent()
    End Sub

#End Region

#Region " SQL Connection String "
    Public ReadOnly Property getConnString() As String
        Get
            'Live 
            Return "Server="
        End Get
    End Property
#End Region

#Region " MakeHtml "
    Public Function MakeHtml(ByVal Input As String) As String
        'Parse for <#> and replace with <br />
        Input = Replace(Input, "<#>", "<br>")
        Return Input
    End Function
#End Region

#Region " MakeList "
    Public Function MakeList(ByVal Input As String) As String
        'Parse for <#> and replace with </li><li>
        Input = Replace(Input, "<#>", "</li><li>")
        Return Input
    End Function

#End Region

#Region " Convert DataReader to Data Set "
    Public Shared Function convertDataReaderToDataSet(ByVal reader As SqlDataReader) As DataSet
        Dim ds As DataSet = New DataSet
        Dim schema As DataTable
        Dim data As DataTable
        Dim i As Integer
        Dim dr As DataRow
        Dim dc As DataColumn
        Dim columnName As String

Do
            schema = reader.GetSchemaTable()
            data = New DataTable
            If Not schema Is Nothing Then
                For i = 0 To schema.Rows.Count - 1
                    dr = schema.Rows(i)
                    columnName = dr("ColumnName")
                    If data.Columns.Contains(columnName) Then
                        columnName = columnName + "_" + i.ToString()
                    End If
                    dc = New DataColumn(columnName, CType(dr("DataType"), Type))
                    data.Columns.Add(dc)
                Next

ds.Tables.Add(data)

While reader.Read()
                    dr = data.NewRow()
                    For i = 0 To reader.FieldCount - 1
                        dr(i) = reader.GetValue(i)
                    Next
                    data.Rows.Add(dr)
                End While
            Else
                dc = New DataColumn("RowsAffected")
                data.Columns.Add(dc)
                ds.Tables.Add(data)
                dr = data.NewRow()
                dr(0) = reader.RecordsAffected
                data.Rows.Add(dr)
            End If
        Loop While reader.NextResult()

reader.Close()

Return ds
    End Function
#End Region

#Region " Populate Cities Drop Down "
    Sub PopulateCities(ByVal CountryId As Integer)
        'Get SQL Data
        Dim SQL As String = "tblCity_Cities_by_CountryID"
        Dim params() As SqlParameter = New SqlParameter(0) {}
        params(0) = New SqlParameter("@CountryID", CountryId)
        Dim dsLMCity As SqlClient.SqlDataReader = SqlHelper.ExecuteReader(getConnString, CommandType.StoredProcedure, SQL, params)

'Clear Previous City List
        ddlLMCity.Items.Clear()

'Write New City List
        While dsLMCity.Read
            ddlLMCity.Items.Add(dsLMCity.Item("City"))
        End While
        dsLMCity.Close()
    End Sub
#End Region

#Region " Page Load "
    Private Sub Page_Load(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles MyBase.Load
        'Declare Dataset for Cache
        Dim ds As DataSet
        ds = Cache("data")

If Not IsPostBack Then
            ' Set Dates in Drop Downs
            For i As Integer = 1 To 20
                ddlLMIn.Items.Add(Today.AddDays(i).ToString("D"))
                ddlLMOut.Items.Add(Today.AddDays(i).ToString("D"))
            Next

ddlLMCtry.Items.FindByValue(3)
            PopulateCities(ddlLMCtry.SelectedValue)
            ddlLMIn.Items.FindByValue(Today.AddDays(1).ToStrin  g("D")).Selected = True
            ddlLMOut.Items.FindByValue(Today.AddDays(3).ToStri  ng("D")).Selected = True

Dim CityId As Integer
            CityId = litCityID.Text

'SQL Call
            Dim SQL As String = "Hotels_by_CityID"
            Dim params() As SqlParameter = New SqlParameter(0) {}
            params(0) = New SqlParameter("@CityID", CityId)
            Dim dsCity As SqlClient.SqlDataReader = SqlHelper.ExecuteReader(getConnString, CommandType.StoredProcedure, SQL, params)

'Conver Datareader into a Dataset for Cacheing
            ds = convertDataReaderToDataSet(dsCity)
            Cache("Data") = ds
            dsCity.Close()

rptResults.DataSource = ds
            rptResults.DataBind()
            'set message to say where datacame from
            litMsg.Text = "DB"

Else
            'Bind Cache to repeater
            rptResults.DataSource = Cache("Data")
            rptResults.DataBind()
            litMsg.Text = "C"
        End If
        'Time of cache
        litTime.Text = Now
    End Sub
#End Region

#Region " Btn Search Click "
    Private Sub btnSearch_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles btnSearch.Click
        Dim inDate As DateTime
        Dim outDate As DateTime

inDate = ddlLMIn.SelectedValue
        outDate = ddlLMOut.SelectedValue
       
        'For testing.. 
        'Response.Write(inDate)
        'Response.Write(outDate)
      Response.Redirect("http://www.website.com/default.aspx?city=" & ddlLMCity.SelectedValue & "&indate=" & inDate.ToString("yyyy-M-d") & "&outdate=" & outDate.ToString("yyyy-M-d"))

End Sub
#End Region

#Region " Drop Down List Change "
    Private Sub ddlLMCtry_SelectedIndexChanged(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles ddlLMCtry.SelectedIndexChanged
        PopulateCities(ddlLMCtry.SelectedValue)
    End Sub
#End Region

End Class


Imports System.Data.SqlClient

Public Class LocPage
    Inherits System.Web.UI.Page

#Region " Web Form Designer Generated Code "

    'This call is required by the Web Form Designer.
    Protected WithEvents rptResults As System.Web.UI.WebControls.Repeater
    Protected WithEvents litCityID As System.Web.UI.WebControls.Literal
    Protected WithEvents litTime As System.Web.UI.WebControls.Literal
    Protected WithEvents litMsg As System.Web.UI.WebControls.Literal
    Protected WithEvents ddlLMIn As System.Web.UI.WebControls.DropDownList
    Protected WithEvents ddlLMOut As System.Web.UI.WebControls.DropDownList
    Protected WithEvents ddlLMCtry As System.Web.UI.WebControls.DropDownList
    Protected WithEvents ddlLMCity As System.Web.UI.WebControls.DropDownList
    Protected WithEvents btnSearch As System.Web.UI.WebControls.Button

    <System.Diagnostics.DebuggerStepThrough()> Private Sub InitializeComponent()

    End Sub

    'NOTE: The following placeholder declaration is required by the Web Form Designer.
    'Do not delete or move it.
    Private designerPlaceholderDeclaration As System.Object

    Private Sub Page_Init(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles MyBase.Init
        'CODEGEN: This method call is required by the Web Form Designer
        'Do not modify it using the code editor.
        InitializeComponent()
    End Sub

#End Region

#Region " SQL Connection String "
    Public ReadOnly Property getConnString() As String
        Get
            'Live 
            Return "Server="
        End Get
    End Property
#End Region

#Region " MakeHtml "
    Public Function MakeHtml(ByVal Input As String) As String
        'Parse for <#> and replace with <br />
        Input = Replace(Input, "<#>", "<br>")
        Return Input
    End Function
#End Region

#Region " MakeList "
    Public Function MakeList(ByVal Input As String) As String
        'Parse for <#> and replace with </li><li>
        Input = Replace(Input, "<#>", "</li><li>")
        Return Input
    End Function

#End Region

#Region " Convert DataReader to Data Set "
    Public Shared Function convertDataReaderToDataSet(ByVal reader As SqlDataReader) As DataSet
        Dim ds As DataSet = New DataSet
        Dim schema As DataTable
        Dim data As DataTable
        Dim i As Integer
        Dim dr As DataRow
        Dim dc As DataColumn
        Dim columnName As String

        Do
            schema = reader.GetSchemaTable()
            data = New DataTable
            If Not schema Is Nothing Then
                For i = 0 To schema.Rows.Count - 1
                    dr = schema.Rows(i)
                    columnName = dr("ColumnName")
                    If data.Columns.Contains(columnName) Then
                        columnName = columnName + "_" + i.ToString()
                    End If
                    dc = New DataColumn(columnName, CType(dr("DataType"), Type))
                    data.Columns.Add(dc)
                Next

                ds.Tables.Add(data)

                While reader.Read()
                    dr = data.NewRow()
                    For i = 0 To reader.FieldCount - 1
                        dr(i) = reader.GetValue(i)
                    Next
                    data.Rows.Add(dr)
                End While
            Else
                dc = New DataColumn("RowsAffected")
                data.Columns.Add(dc)
                ds.Tables.Add(data)
                dr = data.NewRow()
                dr(0) = reader.RecordsAffected
                data.Rows.Add(dr)
            End If
        Loop While reader.NextResult()

        reader.Close()

        Return ds
    End Function
#End Region

#Region " Populate Cities Drop Down "
    Sub PopulateCities(ByVal CountryId As Integer)
        'Get SQL Data
        Dim SQL As String = "tblCity_Cities_by_CountryID"
        Dim params() As SqlParameter = New SqlParameter(0) {}
        params(0) = New SqlParameter("@CountryID", CountryId)
        Dim dsLMCity As SqlClient.SqlDataReader = SqlHelper.ExecuteReader(getConnString, CommandType.StoredProcedure, SQL, params)

        'Clear Previous City List
        ddlLMCity.Items.Clear()

        'Write New City List
        While dsLMCity.Read
            ddlLMCity.Items.Add(dsLMCity.Item("City"))
        End While
        dsLMCity.Close()
    End Sub
#End Region

#Region " Page Load "
    Private Sub Page_Load(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles MyBase.Load
        'Declare Dataset for Cache
        Dim ds As DataSet
        ds = Cache("data")

        If Not IsPostBack Then
            ' Set Dates in Drop Downs
            For i As Integer = 1 To 20
                ddlLMIn.Items.Add(Today.AddDays(i).ToString("D"))
                ddlLMOut.Items.Add(Today.AddDays(i).ToString("D"))
            Next

            ddlLMCtry.Items.FindByValue(3)
            PopulateCities(ddlLMCtry.SelectedValue)
            ddlLMIn.Items.FindByValue(Today.AddDays(1).ToStrin  g("D")).Selected = True
            ddlLMOut.Items.FindByValue(Today.AddDays(3).ToStri  ng("D")).Selected = True

            Dim CityId As Integer
            CityId = litCityID.Text

            'SQL Call
            Dim SQL As String = "Hotels_by_CityID"
            Dim params() As SqlParameter = New SqlParameter(0) {}
            params(0) = New SqlParameter("@CityID", CityId)
            Dim dsCity As SqlClient.SqlDataReader = SqlHelper.ExecuteReader(getConnString, CommandType.StoredProcedure, SQL, params)

            'Conver Datareader into a Dataset for Cacheing
            ds = convertDataReaderToDataSet(dsCity)
            Cache("Data") = ds
            dsCity.Close()

            rptResults.DataSource = ds
            rptResults.DataBind()
            'set message to say where datacame from
            litMsg.Text = "DB"

        Else
            'Bind Cache to repeater
            rptResults.DataSource = Cache("Data")
            rptResults.DataBind()
            litMsg.Text = "C"
        End If
        'Time of cache
        litTime.Text = Now
    End Sub
#End Region

#Region " Btn Search Click "
    Private Sub btnSearch_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles btnSearch.Click
        Dim inDate As DateTime
        Dim outDate As DateTime

        inDate = ddlLMIn.SelectedValue
        outDate = ddlLMOut.SelectedValue
       
        'For testing.. 
        'Response.Write(inDate)
        'Response.Write(outDate)
      Response.Redirect("http://www.website.com/default.aspx?city=" & ddlLMCity.SelectedValue & "&indate=" & inDate.ToString("yyyy-M-d") & "&outdate=" & outDate.ToString("yyyy-M-d"))

    End Sub
#End Region

#Region " Drop Down List Change "
    Private Sub ddlLMCtry_SelectedIndexChanged(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles ddlLMCtry.SelectedIndexChanged
        PopulateCities(ddlLMCtry.SelectedValue)
    End Sub
#End Region

End Class

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