Question

ASP.NET: Retrieving DropDownList in Gridview RowUpdating event

Asked by: BigBadJock

I have a problem, with GridView and TemplateFields. We have an application which creates maintenance screens based on an xml configuration file. The xml describes which fields to show, etc. This all works

However, we have a new requirement to add DropDownLists to some columns to enforce data integrity.

I have therefore added the relevant xml, and when creating the grid, create the column as a TemplateField and the EditItem as a DropDownList with its own SqlDataSource.

So far so good, this all works, the grid is displayed, the DropDownList appears, filled with the correct data, shows the correct initial item and lets the user select another.

Here is where I have problems. The when trying to get the value from the DropDownList in the RowUpdating event, I cant find it. Ive used FindControl to no avail. I create a RecursiveFindControl method that ran through every control on the page, and it cant find it. Ive tried peeking in the cell controls in the debugger and its just not there.

Can anyone help? Ive duplicated it in a simpler test page, with a test database.

<%@ Page Language="C#" AutoEventWireup="true" CodeBehind="test2.aspx.cs" Inherits="WareHouseAdmin.test2" %>
<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">
 
<html xmlns="http://www.w3.org/1999/xhtml" >
<head runat="server">
    <title></title>
</head>
<body>
    <form id="form1" runat="server">
    <div>
        <asp:GridView ID="GridView1" runat="server" AutoGenerateColumns="False" AutoGenerateEditButton="True" onrowcancelingedit="GridView1_RowCancelingEdit" onrowediting="GridView1_RowEditing" onrowupdated="GridView1_RowUpdated" onrowupdating="GridView1_RowUpdating" DataSourceID="SqlDataSource1">
        </asp:GridView>
    </div>
    <asp:SqlDataSource ID="SqlDataSource1" runat="server" onupdated="SqlDataSource1_Updated" onupdating="SqlDataSource1_Updating"></asp:SqlDataSource>
    <asp:SqlDataSource ID="SqlDataSource2" runat="server"></asp:SqlDataSource>
    </form>
</body>
</html>
 
 
-----------------------------
 
 
 
using System;
using System.Collections.Generic;
using System.Configuration;
using System.Linq;
using System.Web;
using System.Web.UI;
using System.Web.UI.WebControls;
 
namespace WareHouseAdmin
{
    public partial class test2 : System.Web.UI.Page
    {
        
        protected void Page_Init(object sender, EventArgs e)
        {
            SetupData();
        }
 
        protected void Page_Load(object sender, EventArgs e)
        {
            BuildGrid();
            if (!IsPostBack)
            {
                BindGrid();
            }
        }
 
        private void SetupData()
        {
            string connection = ConfigurationManager.ConnectionStrings["warehouseConnectionString"].ConnectionString;
            this.SqlDataSource1.ConnectionString = connection;
            this.SqlDataSource1.SelectCommand = "select * from songs";
            this.SqlDataSource1.UpdateCommand = "UPDATE [Songs] SET [AlbumId]=@albumId, [ArtistId]=@artistId, [SongTitle] = @SongTitle, [notes] = @notes WHERE [ID] = @ID";
            this.SqlDataSource1.UpdateParameters.Clear();
 
            this.SqlDataSource2.ConnectionString = connection;
            this.SqlDataSource2.SelectCommand = "select * from albums";
        }
 
        private void BindGrid()
        {
            this.GridView1.DataBind();
        }
 
        private void BuildGrid()
        {
            this.GridView1.Columns.Clear();
            AddColumn("id", "id", "Int32");
            //AddColumn("Album", "albumId", "Int32");
            AddDropDownColumn("Album", "albumId","id","name",SqlDataSource2);
            AddColumn("Artist", "artistId", "Int32");
            AddColumn("Title", "songTitle","String");
            AddColumn("Notes", "notes", "String");
 
            this.GridView1.DataKeyNames = new string[] { "id" };
 
        }
 
 
        private void AddColumn(string header, string name, string dataType)
        {
            BoundField bf = new BoundField();
            bf.HeaderText = header;
            bf.DataField = name;
            bf.SortExpression = name;
            bf.ReadOnly = false;
            bf.HtmlEncode = true;
            this.GridView1.Columns.Add(bf);
 
 
            TypeCode tc = (TypeCode)Enum.Parse(typeof(TypeCode), dataType);
            Parameter p = new Parameter(name, tc);
            this.SqlDataSource1.UpdateParameters.Add(p);
 
        }
 
        private void AddDropDownColumn(string header, string name, string valueColumn, string displayColumn, SqlDataSource dataSource)
        {
            TemplateField tf = new TemplateField();
            tf.HeaderText = header;
            tf.ItemTemplate = new DDLTemplate(ListItemType.Item, name, null, null, null);
            tf.EditItemTemplate = new DDLTemplate(ListItemType.EditItem, name, valueColumn, displayColumn, dataSource );
            this.GridView1.Columns.Add(tf);
 
            TypeCode tc = (TypeCode)Enum.Parse(typeof(TypeCode), "Int32");
            Parameter p = new Parameter(name, tc);
            this.SqlDataSource1.UpdateParameters.Add(p);
 
        }
 
        protected void GridView1_RowEditing(object sender, GridViewEditEventArgs e)
        {
            this.GridView1.EditIndex = e.NewEditIndex;
            BindGrid();
        }
 
        protected void GridView1_RowUpdating(object sender, GridViewUpdateEventArgs e)
        {
            GridViewRow row = this.GridView1.Rows[e.RowIndex];
            Control foundControl = RecursiveFindControl(row, "GridView1$ctl07$albumId_ddl");
            if (foundControl != null)
            {
                DropDownList ddl = (DropDownList)foundControl;
                string val = ddl.SelectedValue;
                e.NewValues.Add("albumId", val);
            }
            BindGrid();
        }
 
        private Control RecursiveFindControl(Control root, string id)
        {
            if (root.ID != null)
            {
                if (root.ID.EndsWith(id))
                {
                    return root;
                }
            }
            if (root.ClientID != null)
            {
                if (root.ClientID.EndsWith(id))
                {
                    return root;
                }
            }
            foreach (Control subControl in root.Controls)
            {
                Control foundControl = RecursiveFindControl(subControl, id);
                if (foundControl != null)
                {
                    return foundControl;
                }
            }
            return null;
        }
 
        protected void GridView1_RowUpdated(object sender, GridViewUpdatedEventArgs e)
        {
        }
 
        protected void GridView1_RowCancelingEdit(object sender, GridViewCancelEditEventArgs e)
        {
            this.GridView1.EditIndex = -1;
            BindGrid();
        }
 
        protected void SqlDataSource1_Updated(object sender, SqlDataSourceStatusEventArgs e)
        {
            if (e.Exception != null)
            {
                e.ExceptionHandled = true;
            }
        }
 
        protected void SqlDataSource1_Updating(object sender, SqlDataSourceCommandEventArgs e)
        {
            System.Console.WriteLine(e.Command);
 
        }
 
    }
 
    public class DDLTemplate : System.Web.UI.Page, ITemplate
    {
        ListItemType templateType;
        string column;
        string valueColumn;
        string displayColumn;
        SqlDataSource dataSource;
 
        public DDLTemplate(ListItemType type, string column, string valueColumn, string displayColumn, SqlDataSource dataSource)
        {
            this.templateType = type;
            this.column = column;
            this.valueColumn = valueColumn;
            this.displayColumn = displayColumn;
            this.dataSource = dataSource;
        }
 
        public void InstantiateIn(System.Web.UI.Control container)
        {
            switch (templateType)
            {
                case ListItemType.Header:
                    break;
 
                case ListItemType.Item:
                    Literal lc = new Literal();
                    lc.DataBinding += new EventHandler(lc_DataBinding);
                    container.Controls.Add(lc);
                    break;
 
                case ListItemType.EditItem:
                    DropDownList ddl = new DropDownList();
                    ddl.ID = "albumId_ddl";
                    ddl.DataValueField = this.valueColumn;
                    ddl.DataTextField = this.displayColumn;
                    ddl.DataSource = this.dataSource;
                    ddl.DataBinding += new EventHandler(ddl_DataBinding);
                    ddl.SelectedIndexChanged += new EventHandler(ddl_SelectedIndexChanged);
                    container.Controls.Add(ddl);
                    break;
 
                case ListItemType.Footer:
                    break;
 
            }
        }
 
        void ddl_SelectedIndexChanged(object sender, EventArgs e)
        {
            DropDownList ddl = (DropDownList)sender;
            Session["albumId_val"] = ddl.SelectedValue;
        }
 
        void lc_DataBinding(object sender, EventArgs e)
        {
            Literal lc = (Literal)sender;
            GridViewRow row = (GridViewRow)lc.NamingContainer;
            string text = DataBinder.Eval(row.DataItem, this.column).ToString();
            lc.Text = text;
        }
 
        void ddl_DataBinding(object sender, EventArgs e)
        {
            DropDownList ddl = (DropDownList)sender;
            GridViewRow row = (GridViewRow)ddl.NamingContainer;
            string id = DataBinder.Eval(row.DataItem, column).ToString();
            ddl.SelectedValue = id;
            ddl.SelectedIndexChanged += new EventHandler(ddl_SelectedIndexChanged);
 
        }
 
    }
 
}

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Asked On: 2009-03-06 at 05:29:56ID24205485
Tags: ASP.NET; .Net
,; C#; GridView; DropDownList
Topics: Programming for ASP.NET
,; C# Programming Language
,; .NET Framework 3.x versions
Participating Experts: 2
Points: 0
Comments: 27

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Answers

by: davrob60Posted on 2009-03-06 at 06:31:03ID: 23816835

instead use e.RowIndex to extact the rox from the gridview and use find control on the extracted row

http://msdn.microsoft.com/en-us/library/system.web.ui.webcontrols.gridviewupdateeventargs_properties.aspx

here an exemple.

http://www.daniweb.com/forums/thread143909.html

and in case you prefear vb version:

http://social.msdn.microsoft.com/Forums/en-US/vblanguage/thread/2536897b-a251-4f79-a8b9-b3bc9100f4b7/

by: BigBadJockPosted on 2009-03-06 at 06:38:06ID: 23816916

Thanks, but I have tried using e.RowIndex and EditIndex. I have also tried doing a recursive check on the Grid and even the whole Page, but still cannot find the DropDownList.

by: davrob60Posted on 2009-03-06 at 06:43:20ID: 23816977

if you are trying to find it using "GridView1$ctl07$albumId_ddl", you wont find it. but if you are using "albumId_ddl" you will find it as you are in the correct container.

by: BigBadJockPosted on 2009-03-06 at 06:48:38ID: 23817030

Sorry, that was test code I left in. I have been searching for albumId_ddl, but after checking the html source, I thought I'd try the generated name as well. Still no luck.

by: ragi0017Posted on 2009-03-06 at 06:50:00ID: 23817043

did you try the code ro rowindex as suggested above and in the line below taken from the below mentioned link
drdList = (DropDownList)(GridView1.Rows[ e.RowIndex ].Cells[1].FindControl( "DropDownList1" ));
http://programming.top54u.com/post/Edit-Update-GridView-DropDownList-SelectedValue.aspx

by: davrob60Posted on 2009-03-06 at 06:55:34ID: 23817087

did you try this?

protected void GridView1_RowUpdating(object sender, GridViewUpdateEventArgs e)
        {
                        DropDownList ddl = (DropDownList)(GridView1.Rows[ e.RowIndex ].Cells[1].FindControl( "albumId_ddl" ));
            if (ddl != null)
            {
                                string val = ddl.SelectedValue;
                                e.NewValues.Add("albumId", val);
            }
            BindGrid();
        }

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by: davrob60Posted on 2009-03-06 at 06:58:16ID: 23817110

sorry i think you dont need the "Cells[1]" part

protected void GridView1_RowUpdating(object sender, GridViewUpdateEventArgs e)
        {
                        DropDownList ddl = (DropDownList)(GridView1.Rows[ e.RowIndex ].FindControl( "albumId_ddl" ));
            if (ddl != null)
            {
                                string val = ddl.SelectedValue;
                                e.NewValues.Add("albumId", val);
            }
            BindGrid();
        }

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by: BigBadJockPosted on 2009-03-06 at 07:02:43ID: 23817151

Yes, I am trying that, returns null.


            DropDownList ddl1 = (DropDownList)GridView1.Rows[e.RowIndex].FindControl("albumID_ddl");

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by: ragi0017Posted on 2009-03-06 at 07:04:02ID: 23817168

did you try my suggestion
drdList = (DropDownList)(GridView1.Rows[ e.RowIndex ].Cells[1].FindControl( "DropDownList1" ));

by: davrob60Posted on 2009-03-06 at 07:06:16ID: 23817193

OK than you need that column thing. if i<m correct, you ddl is in column 2, so it should be

DropDownList ddl = (DropDownList)(GridView1.Rows[ e.RowIndex ].Cells[1].FindControl( "albumId_ddl" ));

by: davrob60Posted on 2009-03-06 at 07:07:36ID: 23817210

yes, you where right ragi0017, but DropDownList1 = albumId_ddl for him

by: ragi0017Posted on 2009-03-06 at 07:09:08ID: 23817228

so what .... i think that the aurhor can understand that much.... i just want to give the logic to fix the problem which i think i have

by: davrob60Posted on 2009-03-06 at 07:17:09ID: 23817326

ragi0017, I said you where right, but at the point we are in this question, I just want to be sure the author test it with the right code. I`m not telling you you or the author diden`t undrestand this.

by: BigBadJockPosted on 2009-03-06 at 07:17:38ID: 23817335

I have tried that. No Luck.

I've just drilled down into the cell, in debug, and the TemplateField is showing the EditItemTemplate as null. In fact so is the ItemTemplate.

by: davrob60Posted on 2009-03-06 at 07:26:26ID: 23817432

well, EditItemTemplate is null because you set it dynamicly, it`s not using a EditItemTemplate.
What you should check is the content of GridView1.Rows[ e.RowIndex ]

i now suspect it<s has somthing to do with the BindGrid(); call, it i correctly understant it, the grid is constructed (and the dropdown) at this point. what if you call the BindGrid BEFORE finding the ddl?

by: davrob60Posted on 2009-03-06 at 07:28:49ID: 23817458

Sorry, you have BuildGrid() call on Page_Load. it should not be this...

any idea ragi0017?

by: BigBadJockPosted on 2009-03-06 at 07:46:09ID: 23817688

If I call the BindGrid() at the start of RowUpdating then the DropDownList is available, but the selectedValue is lost.

From what was said in the other comment, should I be calling the BuildGrid from somewhere other than Page_Load()?

by: davrob60Posted on 2009-03-06 at 07:55:01ID: 23817787

No i dont think the page load is the problem, but we are getting closer to the source of the problem. i<m surprise the BindGrid() make the DropDownList "appear".

What happen if you leave the BindGrid(); at the end but call BuildGrid(); before finding the ddl? I worry it will still dont have your new value, but let`s try.

The other solution is to drop that dynamic control creation and uses standard item and edit templates (declaratively in the aspx file)

by: BigBadJockPosted on 2009-03-06 at 08:11:06ID: 23817971

With just BuildGrid() called, then the ddl is null.

Unfortunatley, I can't drop the dynamic creation, as this app is used to maintain three different systems, and being defined by an XML configuration file, means that the page can be used to maintain multiple tables.

by: davrob60Posted on 2009-03-06 at 08:17:23ID: 23818054

I jsut noticed this code.

void ddl_SelectedIndexChanged(object sender, EventArgs e)
{
DropDownList ddl = (DropDownList)sender;
Session["albumId_val"] = ddl.SelectedValue;
}

so i guess you are doing something like this has a workaround.

string val = Session["albumId_val"]

e.NewValues.Add("albumId", val);

if not, it could be a solution, since we cannot find the control right now...

by: BigBadJockPosted on 2009-03-06 at 08:20:17ID: 23818086

I had tried that but the SelectedIndexChanged was never called. I haven't investigated why not yet.

by: davrob60Posted on 2009-03-06 at 08:30:12ID: 23818200

That is wonderfull... (sarcasm)

I was thinking of retriving the ddl value trough the viewstate and i found this.

http://msdn.microsoft.com/en-us/library/ms972976.aspx

So i got another idea, what if you call the BuildGrid in the page init instead of page load?

by: BigBadJockPosted on 2009-03-11 at 08:57:42ID: 23858815

After investigation, it looks like the SelectedIndexChanged is not called because on the postback with update, the DropDownList doesn't exists, therefore the event doesn't exist.

As a workaround, I can add a javascript onchange event to the DropDownList which is called when the value changes. Is there a way I can pass this value back to the server and use it?

by: davrob60Posted on 2009-03-11 at 09:05:25ID: 23858917

Asp.net generate a javascript function with the name "__doPostBack". this is the function that is called by all control when sending information to the server. So, you could use it in the javascript onchange event.

http://aspalliance.com/895_Understanding_the_JavaScript___doPostBack_Function.all

by: BigBadJockPosted on 2009-03-12 at 04:30:00ID: 23866991

I have it working. I removed the isPostback check around the bindgrid on the pageLoad. Here is the working code.

<%@ Page Language="C#" AutoEventWireup="true" CodeBehind="test2.aspx.cs" Inherits="WareHouseAdmin.test2" %>
<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">
 
<html xmlns="http://www.w3.org/1999/xhtml" >
<head runat="server">
    <title></title>
</head>
<body>
    <form id="form1" runat="server">
    <div>
        <asp:GridView ID="GridView1" runat="server" AutoGenerateColumns="False" AutoGenerateEditButton="True" onrowcancelingedit="GridView1_RowCancelingEdit" onrowediting="GridView1_RowEditing" onrowupdated="GridView1_RowUpdated" onrowupdating="GridView1_RowUpdating" DataSourceID="SqlDataSource1" >
        </asp:GridView>
    </div>
    <asp:SqlDataSource ID="SqlDataSource1" runat="server" onupdated="SqlDataSource1_Updated" onupdating="SqlDataSource1_Updating"></asp:SqlDataSource>
    <asp:SqlDataSource ID="SqlDataSource2" runat="server"></asp:SqlDataSource>
    </form>
</body>
</html>
 
----------------------
 
 
using System;
using System.Collections.Generic;
using System.Configuration;
using System.Linq;
using System.Web;
using System.Web.UI;
using System.Web.UI.WebControls;
using System.IO;
 
namespace WareHouseAdmin
{
    public partial class test2 : System.Web.UI.Page
    {
        
        protected void Page_Init(object sender, EventArgs e)
        {
            SetupData();
        }
 
        protected void Page_Load(object sender, EventArgs e)
        {
            BuildGrid();
            BindGrid();
        }
 
        private void SetupData()
        {
            string connection = ConfigurationManager.ConnectionStrings["warehouseConnectionString"].ConnectionString;
            this.SqlDataSource1.ConnectionString = connection;
            this.SqlDataSource1.SelectCommand = "select s.*, ar.name as artist, al.name as album from songs s,artists ar,albums al where ar.id = s.artistId and al.id = s.albumId";
            this.SqlDataSource1.UpdateCommand = "UPDATE [Songs] SET [AlbumId]=@albumId, [ArtistId]=@artistId, [SongTitle] = @SongTitle, [notes] = @notes WHERE [ID] = @ID";
            this.SqlDataSource1.UpdateParameters.Clear();
 
            this.SqlDataSource2.ConnectionString = connection;
            this.SqlDataSource2.SelectCommand = "select * from albums";
        }
 
        private void BindGrid()
        {
            this.GridView1.DataBind();
        }
 
        private void BuildGrid()
        {
            this.GridView1.Columns.Clear();
            this.GridView1.DataKeyNames = new string[] { "id" };
 
            AddColumn("id", "id", "Int32");
            //AddColumn("Album", "albumId", "Int32");
            AddDropDownColumn("Album", "albumId","id","name",SqlDataSource2);
            AddColumn("Artist", "artistId", "Int32");
            AddColumn("Title", "songTitle","String");
            AddColumn("Notes", "notes", "String");
 
 
        }
 
 
        private void AddColumn(string header, string name, string dataType)
        {
            BoundField bf = new BoundField();
            bf.HeaderText = header;
            bf.DataField = name;
            bf.SortExpression = name;
            bf.ReadOnly = false;
            bf.HtmlEncode = true;
            this.GridView1.Columns.Add(bf);
 
 
            TypeCode tc = (TypeCode)Enum.Parse(typeof(TypeCode), dataType);
            Parameter p = new Parameter(name, tc);
            this.SqlDataSource1.UpdateParameters.Add(p);
 
        }
 
        private void AddDropDownColumn(string header, string name, string valueColumn, string displayColumn, SqlDataSource dataSource)
        {
            TemplateField tf = new TemplateField();
            tf.HeaderText = header;
            tf.ItemTemplate = new DDLTemplate(ListItemType.Item, name, null, null, null);
            tf.EditItemTemplate = new DDLTemplate(ListItemType.EditItem, name, valueColumn, displayColumn, dataSource );
            this.GridView1.Columns.Add(tf);
 
            TypeCode tc = (TypeCode)Enum.Parse(typeof(TypeCode), "Int32");
            Parameter p = new Parameter(name, tc);
            this.SqlDataSource1.UpdateParameters.Add(p);
 
        }
 
        protected void GridView1_RowEditing(object sender, GridViewEditEventArgs e)
        {
            this.GridView1.EditIndex = e.NewEditIndex;
            BindGrid();
        }
 
        protected void GridView1_RowUpdating(object sender, GridViewUpdateEventArgs e)
        {
            DropDownList ddl = (DropDownList)GridView1.Rows[e.RowIndex].FindControl("albumID_ddl");
            string val = ddl.SelectedValue;
            e.NewValues.Add("albumId", val);
            BindGrid();
        }
 
        protected void GridView1_RowUpdated(object sender, GridViewUpdatedEventArgs e)
        {
        }
 
        protected void GridView1_RowCancelingEdit(object sender, GridViewCancelEditEventArgs e)
        {
            this.GridView1.EditIndex = -1;
            BindGrid();
        }
 
        protected void SqlDataSource1_Updated(object sender, SqlDataSourceStatusEventArgs e)
        {
            if (e.Exception != null)
            {
                e.ExceptionHandled = true;
            }
        }
 
        protected void SqlDataSource1_Updating(object sender, SqlDataSourceCommandEventArgs e)
        {
            System.Console.WriteLine(e.Command);
 
        }
    }
 
    public class DDLTemplate : System.Web.UI.Page, ITemplate
    {
        ListItemType templateType;
        string column;
        string valueColumn;
        string displayColumn;
        SqlDataSource dataSource;
 
        public DDLTemplate(ListItemType type, string column, string valueColumn, string displayColumn, SqlDataSource dataSource)
        {
            this.templateType = type;
            this.column = column;
            this.valueColumn = valueColumn;
            this.displayColumn = displayColumn;
            this.dataSource = dataSource;
        }
 
        public void InstantiateIn(System.Web.UI.Control container)
        {
            switch (templateType)
            {
                case ListItemType.Header:
                    break;
 
                case ListItemType.Item:
                    Literal lc = new Literal();
                    lc.DataBinding += new EventHandler(lc_DataBinding);
                    container.Controls.Add(lc);
                    break;
 
                case ListItemType.EditItem:
                    DropDownList ddl = new DropDownList();
                    ddl.ID = "albumId_ddl";
                    ddl.DataValueField = this.valueColumn;
                    ddl.DataTextField = this.displayColumn;
                    ddl.DataSource = this.dataSource;
                    ddl.DataBinding += new EventHandler(ddl_DataBinding);
                    ddl.AutoPostBack = true;
                    container.Controls.Add(ddl);
                    break;
 
                case ListItemType.Footer:
                    break;
 
            }
        }
 
        void lc_DataBinding(object sender, EventArgs e)
        {
            Literal lc = (Literal)sender;
            GridViewRow row = (GridViewRow)lc.NamingContainer;
            string text = DataBinder.Eval(row.DataItem, "Album").ToString();
            lc.Text = text;
        }
 
        void ddl_DataBinding(object sender, EventArgs e)
        {
            DropDownList ddl = (DropDownList)sender;
            GridViewRow row = (GridViewRow)ddl.NamingContainer;
            string id = DataBinder.Eval(row.DataItem, column).ToString();
            ddl.SelectedValue = id;
        }
 
    }
 
}

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Select all Open in new window

by: davrob60Posted on 2009-03-12 at 05:54:59ID: 23867633

i<m suprise it work. Anyway, i<m galg you found your solution.

by: davrob60Posted on 2009-03-12 at 05:55:17ID: 23867635

oops

galg =glad

20120131-EE-VQP-002

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Question

ASP.NET: Retrieving DropDownList in Gridview RowUpdating event

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ASP.NET; .Net

C#; GridView; DropDownList

Programming for ASP.NET

C# Programming Language

.NET Framework 3.x versions

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