Hi there, I started wrox chat server last night. Everything is working fine. Except this part. It says cannot convert string to int.Please check this

if (!IsPostBack )
        {

            DataSet dsChatRooms;
            dsChatRooms = ChatRoom.GetChatRoomList();
            DataTable dtChatRoom;
            int currentRow = 0;
            dtChatRoom = dsChatRooms.Tables[0];
            //DataRow drChatRoom;
            int lastCategoryID = 0;


            foreach (DataRow drChatRoom in dtChatRoom.Rows)
            {

 int CategoryId = dtChatRoom.Rows[currentRow].ItemArray["CatID"].ToString();
 String CategoryName = dtChatRoom.Rows[currentRow].ItemArray["CatName"].ToString();
 int RoomId = dtChatRoom.Rows[currentRow].ItemArray["RoomID"].ToString();
String RoomName = dtChatRoom.Rows[currentRow].ItemArray["RoomName"].ToString();

                if (CategoryId != lastCategoryID)
                {

                  TreeView1.Nodes.Add(new TreeNode(CategoryName, CategoryId.ToString()));
                }
                currentRow = currentRow + 1;
                lastCategoryID = CategoryId;
            }
            currentRow = 0;

            foreach (TreeNode mNode in TreeView1.Nodes)
            {

                foreach ( DataRow drChatRoom in dtChatRoom.Select("CatID=" + mNode.Value))
                {
                    if (!drChatRoom.IsNull(0))
                    {
                        int RoomId = drChatRoom.ItemArray["RoomID"].ToString();
                        String RoomName =drChatRoom.ItemArray["RoomName"].ToString();

                        mNode.ChildNodes.Add(new TreeNode("<a href='chatroom.aspx?chatRoomID=" + RoomId.ToString() + "'>" + RoomName + "</a>", RoomId.ToString()));
                    }
                }
sorry for this long code.

regards,
Ossy!

__________________
Surya!

Hi Ossy,

And where (that is, on what line) do you get this error?

Did you type this code, or does it come from the download for the book?

Imar


---------------------------------------
Imar Spaanjaars
http://Imar.Spaanjaars.Com
Everyone is unique, except for me.
Author of ASP.NET 2.0 Instant Results and Beginning Dreamweaver MX / MX 2004

Hey Imar,

I typed this code. The error is being generated in these lines

int CategoryId = dtChatRoom.Rows[currentRow].ItemArray["CatID"].ToString();
 String CategoryName = dtChatRoom.Rows[currentRow].ItemArray["CatName"].ToString();
 int RoomId = dtChatRoom.Rows[currentRow].ItemArray["RoomID"].ToString();
String RoomName = dtChatRoom.Rows[currentRow].ItemArray["RoomName"].ToString();

Take a look at this:

int RoomId = dtChatRoom.Rows[currentRow].ItemArray["RoomID"].ToString();

You're calling ToString which results in a String which you're then assigning to an int. The compiler won't let you do this.

Instead, using (int) or Convert.ToInt32() to cast / convert a value to an integer.

How does the original source from the book look like?

Imar

---------------------------------------
Imar Spaanjaars
http://Imar.Spaanjaars.Com
Everyone is unique, except for me.
Author of ASP.NET 2.0 Instant Results and Beginning Dreamweaver MX / MX 2004