Populate ASP.net DropDown from SharePoint Lists

A simple scenario I had this morning, was to populate ASP.net Web page’s drop downs from a SharePoint list.

A fairly simple task using Microsoft.SharePointOnline.CSOM, until I was faced with the list threshold (which I will cover in another post).

Now, in my aspx page, I had to:

1- Reference the required name spaces

using System.Web.UI.WebControls;
using Microsoft.SharePoint.Client;

2- The method to load the DropDowns

private void LoadData()
        {
            try
            {
                string WebUrl = "https://******.sharepoint.com/sites/****/****/";
                string login = "samir.daoudi@**********";
                string password = "**********";";
                var securePassword = new SecureString();
                foreach (char c in password)
                { securePassword.AppendChar(c); }
                var onlineCredentials = new SharePointOnlineCredentials(login, securePassword);
                using (ClientContext CContext = new ClientContext(WebUrl))
                {
                    CContext.Credentials = onlineCredentials;
                    List ShpList = CContext.Web.Lists.GetByTitle("YOURLISTNAME");
                    CamlQuery CamlQ = CamlQuery.CreateAllItemsQuery(1000);
                    
                    Microsoft.SharePoint.Client.ListItemCollection items = ShpList.GetItems(CamlQ);
                    CContext.Load(items);
                    CContext.ExecuteQuery();
                    C_Company.Items.Clear();
                    foreach (Microsoft.SharePoint.Client.ListItem I in items)
                    {
                        C_Company.Items.Add(new System.Web.UI.WebControls.ListItem() { Text = I["Title"].ToString(), Value = I["ID"].ToString() });
                    }
                }
            }
            catch (Exception exp)
            {
                // Do something with the exception
            }
        }