Error to find control of gridview in method

private void grdProjectBind()
        {
            int userClientID = 0;
            Project ObjProject = new Project();
            try
            {

                foreach (GridView row in grdClient.Rows)
                {
                     userClientID = Convert.ToInt32(((Label)row.FindControl("lbUserClientID")).Text);//error here
                
                }

                   // int userClientID = Convert.ToInt32(((Label) .FindControl("lbUserClientID")).Text);


                ObjProject.UserClientID = userClientID;

                    DataSet ds = new DataSet();
                    ds = ObjProject.GetProjectList();
                    if (ds.Tables[0].Rows.Count != 0)
                    {
                        grdProject.DataSource = ds;
                        grdProject.DataBind();
                        btnAddProject.Visible = false;
                    }
                    else
                    {
                        grdProject.DataBind();
                        btnAddProject.Visible = true;

                    }
                }
            
            catch (Exception)
            {

                throw;
            }
            finally
            {
                ObjProject = null;
            }
        
        
        }