Radgrid with CascadingDropdown

[chithuraj]

Hi,
    I 'm using Radgrid with three dropdowns for each row. Second dropdown will populate based on the first dropdown selection
 and third drop down will populate based on the second drop down selection. (Like Cascading drop down)

Please guide me to do this ....
Any Guidance will be Appreciated!!!!

Thanks
chithuraj.J

[Princy]

Hello Chituraj,

I suppose you have placed your dropdowns in three different TemplateColumns as shown below:
aspx:

<telerik:GridTemplateColumn>
     <ItemTemplate>
           <asp:DropDownList DataSourceID="SqlDataSource1" DataTextField="Continents" ID="DropDownList1" runat="server">
           </asp:DropDownList>
     </ItemTemplate>
</telerik:GridTemplateColumn>
<telerik:GridTemplateColumn>
     <ItemTemplate>
            <asp:DropDownList ID="DropDownList2" runat="server">
            </asp:DropDownList>
     </ItemTemplate>
</telerik:GridTemplateColumn>
<telerik:GridTemplateColumn>
      <ItemTemplate>
            <asp:DropDownList ID="DropDownList3" runat="server">
            </asp:DropDownList>
      </ItemTemplate>
</telerik:GridTemplateColumn>

If so, you can try out the following code to populate one dropdown based on another dropdowns selection:
c#:

protected void RadGrid_ItemCreated(object sender, Telerik.Web.UI.GridItemEventArgs e)
    {
        if (e.Item is GridDataItem)
        {
            GridDataItem dataItem = (GridDataItem)e.Item;

            DropDownList list1 = (DropDownList)dataItem.FindControl("DropDownList1");
            list1.AutoPostBack = true;
            list1.SelectedIndexChanged += new EventHandler(list1_SelectedIndexChanged);

            DropDownList list2 = (DropDownList)dataItem.FindControl("DropDownList2");
            list2.AutoPostBack = true;
            list2.SelectedIndexChanged += new EventHandler(list2_SelectedIndexChanged);
        }
    }

    void list2_SelectedIndexChanged(object sender, EventArgs e)
    {
        GridDataItem item = (GridDataItem)(sender as DropDownList).NamingContainer;
        DropDownList ddl3 = (DropDownList)item.FindControl("DropDownList3");
        ddl3.DataSourceID = "SqlDataSource1";
        ddl3.DataTextField = "Countries";
    }

    void list1_SelectedIndexChanged(object sender, EventArgs e)
    {
        GridDataItem item = (GridDataItem)(sender as DropDownList).NamingContainer;
        DropDownList ddl2 = (DropDownList)item.FindControl("DropDownList2");
        ddl2.DataSourceID = "SqlDataSource1";
        ddl2.DataTextField = "Cities";
    }

You can alter the logic according to your requirement.

Thanks
Princy.

[chithuraj]

Hello Princy,
       Thanks for your kind help. It is working Perfect.

Thanks and regards!
chithuraj.j

[mathieu cupryk]

Do you have a list of all cities?

[Princy]

Hi Mathieu,

 I'm not really sure as to what you require. But if you want to get all the cities corresponding to a particular country then you can actually download City Databases for the corresponding country from the internet, attach it to your database and populate your control accordingly.

Hope this makes sense.. :)
-Princy.

[Jeru Catli]

could you convert it to vb code? thanks in advance..

[Shinu]

Hello Jeru,

Here's the Vb code for to populate one dropdown based on another dropdowns selection:

vb:

Protected Sub RadGrid_ItemCreated(sender As Object, e As Telerik.Web.UI.GridItemEventArgs)
    If TypeOf e.Item Is GridDataItem Then
        Dim dataItem As GridDataItem = DirectCast(e.Item, GridDataItem)

        Dim list1 As DropDownList = DirectCast(dataItem.FindControl("DropDownList1"), DropDownList)
        list1.AutoPostBack = True
        AddHandler list1.SelectedIndexChanged, AddressOf list1_SelectedIndexChanged


        Dim list2 As DropDownList = DirectCast(dataItem.FindControl("DropDownList2"), DropDownList)
        list2.AutoPostBack = True
        AddHandler list2.SelectedIndexChanged, AddressOf list2_SelectedIndexChanged

    End If
End Sub

Sub list2_SelectedIndexChanged(sender As Object, e As EventArgs)
    Dim item As GridDataItem = DirectCast((TryCast(sender, DropDownList)).NamingContainer, GridDataItem)
    Dim ddl3 As DropDownList = DirectCast(item.FindControl("DropDownList3"), DropDownList)
    ddl3.DataSourceID = "SqlDataSource1"
    ddl3.DataTextField = "Countries"
End Sub

Sub list1_SelectedIndexChanged(sender As Object, e As EventArgs)
    Dim item As GridDataItem = DirectCast((TryCast(sender, DropDownList)).NamingContainer, GridDataItem)
    Dim ddl2 As DropDownList = DirectCast(item.FindControl("DropDownList2"), DropDownList)
    ddl2.DataSourceID = "SqlDataSource1"
    ddl2.DataTextField = "Cities"
End Sub

You can also make use of this code conversion tool to convert c# codes to vb and vice versa.

-Shinu.

[Meenakshi]

I want to load some values in Dropdown 2 based on Dropdown 1 selection inside Radgrid.Kindly help.

 

Thanks,

Meenu

[Venkat]

Hi, I am facing similar issue like about using cascading dropdowns in Telerik grid. He I am doing CRUD operations using Telerik grid functionality. While creating a new record I have 1 level of  cascading dropdowns and I could able to load dropdowns successfully. But after selecting the second dropdown and click on submit button, in 'gvResults_InsertCommand' event dropdown selectedvalue is reset to zero (default). If I donot use the SelectedChanged event for drop down, then I am could able to get the selectedvalue. Please help me on this.

[Pavlina]

Hi,

Please refer to the code library below which demonstrates a similar functionality to the one you are looking for:
http://www.telerik.com/support/code-library/using-cascading-radcomboboxes-into-the-radgrid-insert-edit-form

Regards,
Pavlina
Telerik

[Venkat]

Hi, Thanks for your Information. I think here you have used a custom form for Edit form. But my solution is not using the custom form for Edit / Add item. Can you plz provide help on the solution using Edit /Add items in the same grid for getting selectedValue from dropdown control in Add / Update event?

[Pavlina]

Hello,

Then the following example should help you achieve your goal:
http://www.telerik.com/support/code-library/using-related-radcomboboxes-in-radgrid

Regards,
Pavlina
Telerik