reload grid based on drop down list selection

[John]

I am trying to reload a grid view based on a drop down list selection.  Below is my code.  Can someone point me in the right direction?

.VB code:

Imports

 

System

 

Imports

 

System.Configuration

 

Imports

 

System.Data

 

Imports

 

System.Data.SqlClient

 

Imports

 

Telerik.Web.UI

 

Imports

 

System.Configuration.ConfigurationManager

 

Partial

 

Class Mistras_Admin_NDEEquipmentList

 

 

Inherits System.Web.UI.Page

 

 

Dim myConnection As New SqlConnection(AppSettings("Conn"))

 

 

Public Function GetDataTable(ByVal query As String) As DataTable

 

 

Dim ConnString As String = ConfigurationManager.ConnectionStrings("ConnMR").ConnectionString

 

 

Dim conn As SqlConnection = New SqlConnection(ConnString)

 

 

Dim adapter As SqlDataAdapter = New SqlDataAdapter

 

adapter.SelectCommand =

New SqlCommand(query, conn)

 

 

Dim table1 As New DataTable

 

conn.Open()

 

Try

 

adapter.Fill(table1)

 

Finally

 

conn.Close()

 

End Try

 

 

Return table1

 

 

End Function

 

 

Public ReadOnly Property NDEE() As DataTable

 

 

Get

 

 

Dim obj As Object = Me.Session("NDEE")

 

 

If (Not obj Is Nothing) Then

 

 

Return CType(obj, DataTable)

 

 

End If

 

 

Dim myDataTable As DataTable = New DataTable

 

myDataTable = GetDataTable(

"SELECT Equipment.EquipmentID, EquipmentType.EquipmentType, Equipment.Manufacturer, Equipment.Model, Equipment.SerialNo, Equipment.Megahertz, Equipment.ProbeDiameter, Equipment.TypeOrForm, Equipment.Inactive FROM Equipment with (nolock) inner join EquipmentType with (nolock) on Equipment.EquipmentTypeID = EquipmentType.EquipmentTypeID WHERE Equipment.EquipmentID IN (SELECT EquipmentID FROM Equipment_Location_Link WHERE LocationID = " & ddlLocations.SelectedValue & ")")

 

 

Me.Session("NDEE") = myDataTable

 

 

Return myDataTable

 

 

End Get

 

 

End Property

 

 

Protected Sub RadGrid1_NeedDataSource(ByVal source As Object, ByVal e As Telerik.Web.UI.GridNeedDataSourceEventArgs) Handles RadGrid1.NeedDataSource

 

 

Me.RadGrid1.DataSource = Me.NDEE

 

 

Me.NDEE.PrimaryKey = New DataColumn() {Me.NDEE.Columns("EquipmentID")}

 

 

End Sub

 

 

Protected Sub RadGrid1_PreRender(ByVal sender As Object, ByVal e As System.EventArgs) Handles RadGrid1.PreRender

 

 

If Not IsPostBack Then

 

 

'Me.RadGrid1.MasterTableView.Items(1).Edit = True

 

 

Me.RadGrid1.MasterTableView.Rebind()

 

 

End If

 

 

End Sub

 

 

 

Protected Sub RadGrid1_UpdateCommand(ByVal source As Object, ByVal e As Telerik.Web.UI.GridCommandEventArgs) Handles RadGrid1.UpdateCommand

 

 

Dim editedItem As GridEditableItem = CType(e.Item, GridEditableItem)

 

 

Dim MyUserControl As UserControl = CType(e.Item.FindControl(GridEditFormItem.EditFormUserControlID), UserControl)

 

 

'Locate the changed row in the DataSource

 

 

Dim changedRows As DataRow() = Me.NDEE.Select("EquipmentID = " & editedItem.OwnerTableView.DataKeyValues(editedItem.ItemIndex)("EquipmentID"))

 

 

 

If (Not changedRows.Length = 1) Then

 

e.Canceled =

True

 

 

Return

 

 

End If

 

 

'Update new values

 

 

Using updateCommand As New SqlCommand("Update_Equipment", myConnection)

 

updateCommand.CommandType = CommandType.StoredProcedure

updateCommand.Parameters.AddWithValue(

"@EID", editedItem.OwnerTableView.DataKeyValues(editedItem.ItemIndex)("EquipmentID"))

 

updateCommand.Parameters.AddWithValue(

"@ETID", CType(MyUserControl.FindControl("ddlET"), DropDownList).SelectedValue)

 

updateCommand.Parameters.AddWithValue(

"@Man", CType(MyUserControl.FindControl("txtMan"), TextBox).Text)

 

updateCommand.Parameters.AddWithValue(

"@Mod", CType(MyUserControl.FindControl("txtModel"), TextBox).Text)

 

updateCommand.Parameters.AddWithValue(

"@SNo", CType(MyUserControl.FindControl("txtSBN"), TextBox).Text)

 

updateCommand.Parameters.AddWithValue(

"@MHz", CType(MyUserControl.FindControl("txtMHz"), TextBox).Text)

 

updateCommand.Parameters.AddWithValue(

"@PD", CType(MyUserControl.FindControl("txtPD"), TextBox).Text)

 

updateCommand.Parameters.AddWithValue(

"@ToF", CType(MyUserControl.FindControl("txtMPFT"), TextBox).Text)

 

updateCommand.Parameters.AddWithValue(

"@Ina", CType(MyUserControl.FindControl("cbInactive"), CheckBox).Checked)

 

myConnection.Open()

updateCommand.ExecuteNonQuery()

myConnection.Close()

 

End Using

 

 

Dim newValues As Hashtable = New Hashtable

 

newValues(

"Manufacturer") = CType(MyUserControl.FindControl("txtMan"), TextBox).Text

 

newValues(

"Model") = CType(MyUserControl.FindControl("txtModel"), TextBox).Text

 

newValues(

"SerialNo") = CType(MyUserControl.FindControl("txtSBN"), TextBox).Text

 

newValues(

"TypeOrForm") = CType(MyUserControl.FindControl("txtMPFT"), TextBox).Text

 

newValues(

"Megahertz") = CType(MyUserControl.FindControl("txtMHz"), TextBox).Text

 

newValues(

"ProbeDiameter") = CType(MyUserControl.FindControl("txtPD"), TextBox).Text

 

newValues(

"EquipmentType") = CType(MyUserControl.FindControl("ddlET"), DropDownList).SelectedItem.Text

 

newValues(

"Inactive") = CType(MyUserControl.FindControl("cbInactive"), CheckBox).Checked

 

changedRows(0).BeginEdit()

 

Try

 

 

Dim entry As DictionaryEntry

 

 

For Each entry In newValues

 

changedRows(0)(

CType(entry.Key, String)) = entry.Value

 

 

Next

 

changedRows(0).EndEdit()

 

Me.NDEE.AcceptChanges()

 

 

Catch ex As Exception

 

changedRows(0).CancelEdit()

 

Dim lblError As Label = New Label()

 

lblError.Text =

"Unable to update Equipment. Reason: " + ex.Message

 

lblError.ForeColor = System.Drawing.Color.Red

RadGrid1.Controls.Add(lblError)

e.Canceled =

True

 

 

End Try

 

 

End Sub

 

 

Protected Sub RadGrid1_InsertCommand(ByVal source As Object, ByVal e As GridCommandEventArgs) Handles RadGrid1.InsertCommand

 

 

If Session("Insert") = False Then

 

Session(

"Insert") = True

 

 

Exit Sub

 

 

Else

 

Session(

"Insert") = False

 

 

End If

 

 

Dim editedItem As GridEditableItem = CType(e.Item, GridEditableItem)

 

 

Dim userControl As UserControl = CType(e.Item.FindControl(GridEditFormItem.EditFormUserControlID), UserControl)

 

 

'Prepare new row to add it in the DataSource

 

 

Dim newRow As DataRow = Me.NDEE.NewRow

 

 

'Insert new values

 

 

Dim newValues As Hashtable = New Hashtable

 

 

Using insertCommand As New SqlCommand("Insert_Equipment", myConnection)

 

insertCommand.CommandType = CommandType.StoredProcedure

insertCommand.Parameters.AddWithValue(

"@ETID", CType(userControl.FindControl("ddlET"), DropDownList).SelectedValue)

 

insertCommand.Parameters.AddWithValue(

"@Man", CType(userControl.FindControl("txtMan"), TextBox).Text)

 

insertCommand.Parameters.AddWithValue(

"@Mod", CType(userControl.FindControl("txtModel"), TextBox).Text)

 

insertCommand.Parameters.AddWithValue(

"@SNo", CType(userControl.FindControl("txtSBN"), TextBox).Text)

 

insertCommand.Parameters.AddWithValue(

"@MHz", CType(userControl.FindControl("txtMHz"), TextBox).Text)

 

insertCommand.Parameters.AddWithValue(

"@PD", CType(userControl.FindControl("txtPD"), TextBox).Text)

 

insertCommand.Parameters.AddWithValue(

"@ToF", CType(userControl.FindControl("txtMPFT"), TextBox).Text)

 

insertCommand.Parameters.AddWithValue(

"@Ina", CType(userControl.FindControl("cbInactive"), CheckBox).Checked)

 

myConnection.Open()

insertCommand.ExecuteNonQuery()

myConnection.Close()

 

End Using

 

newValues(

"Manufacturer") = CType(userControl.FindControl("txtMan"), TextBox).Text

 

newValues(

"Model") = CType(userControl.FindControl("txtModel"), TextBox).Text

 

newValues(

"SerialNo") = CType(userControl.FindControl("txtSBN"), TextBox).Text

 

newValues(

"TypeOrForm") = CType(userControl.FindControl("txtMPFT"), TextBox).Text

 

newValues(

"Megahertz") = CType(userControl.FindControl("txtMHz"), TextBox).Text

 

newValues(

"ProbeDiameter") = CType(userControl.FindControl("txtPD"), TextBox).Text

 

newValues(

"EquipmentType") = CType(userControl.FindControl("ddlET"), DropDownList).SelectedItem.Text

 

newValues(

"Inactive") = CType(userControl.FindControl("cbInactive"), CheckBox).Checked

 

 

'make sure that unique primary key value is generated for the inserted row

 

newValues(

"EquipmentID") = (CType(Me.NDEE.Rows((Me.NDEE.Rows.Count - 1))("EquipmentID"), Integer) + 1)

 

 

Try

 

 

For Each entry As DictionaryEntry In newValues

 

newRow(

CType(entry.Key, String)) = entry.Value

 

 

Next

 

 

Me.NDEE.Rows.Add(newRow)

 

 

Me.NDEE.AcceptChanges()

 

 

Catch ex As Exception

 

 

Dim lblError As Label = New Label()

 

lblError.Text =

"Unable to insert Equipment. Reason: " + ex.Message

 

lblError.ForeColor = System.Drawing.Color.Red

RadGrid1.Controls.Add(lblError)

e.Canceled =

True

 

 

End Try

 

 

End Sub

 

 

Protected Sub RadGrid1_DeleteCommand(ByVal source As Object, ByVal e As GridCommandEventArgs) Handles RadGrid1.DeleteCommand

 

 

Dim ID As String = (CType(e.Item, GridDataItem)).OwnerTableView.DataKeyValues(e.Item.ItemIndex)("EquipmentID").ToString

 

 

Using deleteCommand As New SqlCommand("Delete_Equipment", myConnection)

 

deleteCommand.CommandType = CommandType.StoredProcedure

deleteCommand.Parameters.AddWithValue(

"@EID", ID)

 

myConnection.Open()

deleteCommand.ExecuteNonQuery()

myConnection.Close()

 

End Using

 

 

Dim NDEETable As DataTable = Me.NDEE

 

 

If Not (NDEETable.Rows.Find(ID) Is Nothing) Then

 

NDEETable.Rows.Find(ID).Delete()

NDEETable.AcceptChanges()

 

End If

 

 

End Sub

 

 

Protected Sub Page_Load(ByVal sender As Object, ByVal e As System.EventArgs) Handles Me.Load

 

 

If IsPostBack = False Then

 

Session(

"Insert") = True

 

 

'Load Locations dropdownlist

 

ddlLocations.Items.Add(

New ListItem(" ", "0"))

 

 

Using selectCommand As New SqlCommand("select_Locations", myConnection)

 

selectCommand.CommandType = CommandType.StoredProcedure

myConnection.Open()

 

Using reader As SqlDataReader = selectCommand.ExecuteReader

 

 

While reader.Read

 

ddlLocations.Items.Add(

New ListItem(reader("WebName"), reader("LocationID")))

 

 

End While

 

 

End Using

 

myConnection.Close()

 

End Using

 

 

End If

 

 

End Sub

 

 

Protected Sub ddlLocations_SelectedIndexChanged(ByVal sender As Object, ByVal e As System.EventArgs) Handles ddlLocations.SelectedIndexChanged

 

 

Me.RadGrid1.DataSource = Me.NDEE

 

 

Me.NDEE.PrimaryKey = New DataColumn() {Me.NDEE.Columns("EquipmentID")}

 

 

Me.RadGrid1.MasterTableView.Rebind()

 

 

End Sub

 

End

 

Class

 

.aspx code:

<

 

asp:Content ID="Content1" ContentPlaceHolderID="PageContent" Runat="Server">

 

 

<telerik:RadCodeBlock ID="RadCodeBlock1" runat="server">

 

 

<script type="text/javascript">

 

 

function RowDblClick(sender, eventArgs) {

 

sender.get_masterTableView().editItem(eventArgs.get_itemIndexHierarchical());

}

 

</script>

 

 

</telerik:RadCodeBlock>

 

 

<telerik:RadAjaxManager ID="RadAjaxManager1" runat="server">

 

 

<AjaxSettings>

 

 

<telerik:AjaxSetting AjaxControlID="RadGrid1">

 

 

<UpdatedControls>

 

 

<telerik:AjaxUpdatedControl ControlID="RadGrid1" />

 

 

</UpdatedControls>

 

 

</telerik:AjaxSetting>

 

 

</AjaxSettings>

 

 

</telerik:RadAjaxManager>

 

 

<asp:DropDownList ID="ddlLocations" runat="server" AutoPostBack="true" /><br /><br />

 

 

<telerik:RadGrid ID="RadGrid1" runat="server" GridLines="None" AllowPaging="True"

 

 

AllowSorting="True" AutoGenerateColumns="False" ShowStatusBar="true" OnPreRender="RadGrid1_PreRender"

 

 

OnNeedDataSource="RadGrid1_NeedDataSource" OnUpdateCommand="RadGrid1_UpdateCommand"

 

 

OnInsertCommand="RadGrid1_InsertCommand" OnDeleteCommand="RadGrid1_DeleteCommand">

 

 

<MasterTableView Width="100%" CommandItemDisplay="Top" DataKeyNames="EquipmentID">

 

 

<Columns>

 

 

<telerik:GridEditCommandColumn UniqueName="EditCommandColumn">

 

 

</telerik:GridEditCommandColumn>

 

 

<telerik:GridBoundColumn UniqueName="Manufacturer" HeaderText="Manufacturer" DataField="Manufacturer">

 

 

</telerik:GridBoundColumn>

 

 

<telerik:GridBoundColumn UniqueName="Model" HeaderText="Model" DataField="Model">

 

 

</telerik:GridBoundColumn>

 

 

<telerik:GridBoundColumn UniqueName="SerialNo" HeaderText="Serial/Batch No." DataField="SerialNo">

 

 

</telerik:GridBoundColumn>

 

 

<telerik:GridBoundColumn UniqueName="TypeOrForm" HeaderText="MT or PT<br/>Form/Type" DataField="TypeOrForm">

 

 

</telerik:GridBoundColumn>

 

 

<telerik:GridBoundColumn UniqueName="Megahertz" HeaderText="MHz" DataField="Megahertz">

 

 

</telerik:GridBoundColumn>

 

 

<telerik:GridBoundColumn UniqueName="ProbeDiameter" HeaderText="Probe<br/>Diameter" DataField="ProbeDiameter">

 

 

</telerik:GridBoundColumn>

 

 

<telerik:GridBoundColumn UniqueName="EquipmentType" HeaderText="Equipment<br/>Type" DataField="EquipmentType">

 

 

</telerik:GridBoundColumn>

 

 

<telerik:GridBoundColumn UniqueName="Inactive" HeaderText="Inactive" DataField="Inactive">

 

 

</telerik:GridBoundColumn>

 

 

<telerik:GridButtonColumn UniqueName="DeleteColumn" Text="Delete" CommandName="Delete" />

 

 

</Columns>

 

 

<EditFormSettings UserControlName="NDEEUpdateForm.ascx" EditFormType="WebUserControl" >

 

 

<EditColumn UniqueName="EditCommandColumn1">

 

 

</EditColumn>

 

 

</EditFormSettings>

 

 

</MasterTableView>

 

 

<ClientSettings>

 

 

<ClientEvents OnRowDblClick="RowDblClick" />

 

 

</ClientSettings>

 

 

</telerik:RadGrid><br />

 

 

<asp:Label ID="test" runat="server" />

 

</

 

asp:Content>

 

[Georgi Krustev]

Hello John,

I noticed that in the SelectedIndexChanged event the RadGrid's DataSource property is assigned and then the Rebind() method is called. Please have in mind that the Rebind will raise the NeedDataSource event and thus all applied changes before it will be lost. In the NeedDataSource event handler the DataSource is applied again. Thus the data source is overridden and all applied changes are lost. To update the grid correctly please consider revising your scenario in order to be able to apply the correct data source in the NeedDataSource event handler.

All the best,
Georgi Krustev
the Telerik team

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[John]

Thanks for the help advice.  Here is what I changed to fix the problem.  Even with doing the Rebind it never re-ran the query since the Session("NDEE") was no longer Nothing so I had to reset it.

 

Protected Sub ddlLocations_SelectedIndexChanged(ByVal sender As Object, ByVal e As System.EventArgs) Handles ddlLocations.SelectedIndexChanged

 

 

Me.Session("NDEE") = Nothing

 

 

Me.RadGrid1.MasterTableView.Rebind()

 

 

End Sub