Question

I have following Gridview:

<asp:GridView ID="GridView1" runat="server" CssClass="table" DataKeyNames="groupId"
          DataSource="<%# dsUserGroupsSelected %>" DataMember="Group" etc....>

and after firing RowDeleting event handler:

protected void GridView1_RowDeleting(object sender, GridViewDeleteEventArgs e)

e.Keys is empty. Moreover, in runtime if I check

dsUserGroupsSelected.Group.PrimaryKey

it is poulated with:

{System.Data.DataColumn[1]}
    [0]: {groupId}

so it’s really odd to me. Am I missing something? I have this kind of a workaround:

int groupId = (int)GridView1.DataKeys[e.RowIndex].Value;

which will work just fine, but I just can’t get it why e.Keys (and e.Values) would be empty!? Any ideas?

Answer 1

It looks like this behaviour is intentional.

From http://forums.asp.net/p/1050092/2128091.aspx

Looking in Reflector at Gridview.HandleDelete(), it appears that
e.Keys and e.Values are only populated if
gridview.IsBoundUsingDataSourceID. That is, if you set the DataSource
in code then none of this will work. Good one, Microsoft! Might have
been useful to mention that in the help perhaps??!! Lachlan

Edit:

I ended up making my own data objects and put them in the app_code folder

ex.

public class CustomDataViews
{
    public class FileQuery
    {
        public class File
        {
            public DateTime CreatedDate { get; set; }
            public string FileName { get; set; }
            public string Path { get; set; }
            public void Delete() { }
        }

        public ArrayList GetFiles()
        {
            System.Collections.ArrayList files = new ArrayList();
            System.IO.DirectoryInfo di = new System.IO.DirectoryInfo(HttpContext.Current.Server.MapPath("~/UserUpload/"));
            foreach (System.IO.FileInfo fi in (from a in di.GetFiles() orderby a.CreationTime descending select a))
            {
                File myFile = new File();
                myFile.CreatedDate = fi.CreationTime;
                myFile.FileName = fi.Name;
                myFile.Path = "/VACWeb/UserUpload/" + fi.Name;
                files.Add(myFile);
            }
            return files;
        }

        public void Delete(string FileName)
        {
            if (FileName != null)
            {
                string path = HttpContext.Current.Server.MapPath("~/UserUpload/") + FileName;
                if (System.IO.File.Exists(path))
                    System.IO.File.Delete(path);
            }
        }
    }
}

aspx

<asp:GridView ID="gvFiles" runat="server" AutoGenerateColumns="False" DataKeyNames="FileName"
    DataSourceID="ods1">
    <Columns>
        <cc:ExtendedCommandField DeleteConfirmationText="Are you sure you wish to delete this file?"
            DeleteText="Delete" ShowDeleteButton="true" />
        <asp:BoundField DataField="CreatedDate" HeaderText="Created Date" DataFormatString="{0:MM/dd/yyyy}" />
        <asp:BoundField DataField="FileName" HeaderText="File Name" />
        <asp:ImageField DataImageUrlField="Path" AlternateText="No Image" HeaderText="Image Preview"
            ControlStyle-Width="100px">
            <ControlStyle Width="100px" />
        </asp:ImageField>
        <asp:BoundField DataField="Path" HeaderText="Path" />
        <asp:HyperLinkField DataNavigateUrlFields="Path" DataTextField="FileName" HeaderText="Link" />
    </Columns>
</asp:GridView>
<asp:ObjectDataSource ID="ods1" runat="server" DeleteMethod="Delete" SelectMethod="GetFiles"
    TypeName="CustomDataViews+FileQuery">
    <DeleteParameters>
        <asp:Parameter Name="FileName" Type="String" />
    </DeleteParameters>
</asp:ObjectDataSource>