Hi,

I'll try to make this straightforward

 
I have a gridview on my aspx page:

                        <asp:GridView ID="ObjectList" runat="server" AutoGenerateColumns="false">
                            <Columns>
                                <asp:BoundField DataField="ObjID" Visible="false"/>
                                <asp:BoundField DataField="EnglishEqu"  HeaderText='<%EngTitle%>' />
                                <asp:TemplateField HeaderText='<%NewTitle%>'>
                                    <ItemTemplate>
                                        <asp:TextBox ID="NewLangEqu" runat="server" MaxLength="255"></asp:TextBox>
                                    </ItemTemplate>
                                </asp:TemplateField>
                            </Columns>
                        </asp:GridView>

I need to bind this list to a collection which is built up in my code behind page:

    code behind:

        int iVal = int.Parse(ListLanguageList.SelectedValue);
        DataSet ds = DatabaseMethods.GetLanguageObjectSet(iVal);

        LanguageGridCollection col = new LanguageGridCollection();

        foreach (DataRow dr in ds.Tables[0].Rows)
        {
            LanguageGridClass lan = new LanguageGridClass();
            lan.ObjID = dr[0].ToString();
            lan.NewLabel = dr[1].ToString();

            //loop through each property in the main resource file
            foreach (PropertyInfo info in (typeof(Resources.ClaimTracking)).GetProperties())
            {
                //if the property is a string then....
                if (info.PropertyType == typeof(string))
                {
                    if (info.Name == lan.ObjID)
                    {
                        lan.EnglishLabel = info.GetValue(info, null).ToString();
                    }
                    col.Add(lan);
                }
            }
        }

        //we now have a list of objIDs and english labels and new labels (if a new label exists)
        ObjectList.DataSource = col;
        ObjectList.DataBind();

custom class and collection codecollection code 

public class LanguageGridClass
{
    public LanguageGridClass() { }

    //the names of the items in the RESX files are unique, ergo each ObjID will be unique
    private string objID;
    public string ObjID
    {
        get
        {
            return objID;
        }
        set
        {
            objID = value;
        }
    }

    private string englishLabel;
    public string EnglishLabel
    {
        get
        {
            return englishLabel;
        }
        set
        {
            englishLabel = value;
        }
    }

    private string newLabel;
    public string NewLabel
    {
        get
        {
            return newLabel;
        }
        set
        {
            newLabel = value;
        }
    }
}

public class LanguageGridCollection : IColumns<LanguageGridClass>
{
    //member variable - used to store the actual list
    private List<LanguageGridClass> Items = new List<LanguageGridClass>();
       
    //override, return the list
    public List<LanguageGridClass> ListOfColumns()
    {
        return Items;
    }

    //add to the list
    public void Add(LanguageGridClass item)
    {
        Items.Add(item);
    }

    //remove from the list
    public void Remove(LanguageGridClass item)
    {
        Items.Remove(item);
    }

    //clear all columns from list
    public void Clear()
    {
        Items.Clear();
    }

    public LanguageGridClass this[int index]
    {
        get
        {
            return ((LanguageGridClass)(this.Items[index]));
        }
        set
        {
            this.Items[index] = value;
        }
    }
}

 

 The error I get is the one in the subject line and it occurs on "ObjectList.DataSource = col;" line

I am not really sure I fully understand the error nor do I know how to go about fixing this.

Anyone with any ideas???

many thanks
 

I believe that your class needs to implement the IDataSource interface (or, IListSource or IEnumerable interfaces) in order for it to be valid to set it as the DataSource property of a GridView.

I would work on making your class implement one of those interfaces. 

Hi

LanguageGridCollection Class should be implements iCollection Interface so defination should be

public class LanguageGridCollection 

                      implements ICollection
 

thanks for the reply

I kinda guess that from the error messgae though. But which interface should I try to implement, (which one is better/more suited to my needs)?

thanks 

Ahh. I think I may have cracked it. The reply about ICollection got me thinking..... and I by inheriting from CollectionBase my error is solved!!

 Thanks for the help