Office 365 how to access list from outside

Question

I need to access a list in office 365 from a page in asp .net, this page is not in the office 365 server and I've tried various methods, for example via the web services in list.asmx but I got problems with the claim authentication, I have not found any practical example on how to do this. How can I insert an item in a list in office 365 from an asp .net site?

update - solution

you can find the solution in Accessing SharePoint Online from a Windows client but I would like to contribute with this code from http://sneakydev.blogspot.com.es/2013/05/using-c-csom-to-interact-with.html :

  Microsoft.SharePoint.Client.ClientContext context;
  context = GetContext();
 getlists();

// and in a class you put this


    // utility class for accessing office365
    private class Configuration
    {
        public static string ServiceSiteUrl = "url";
        public static string ServiceUserName = "[email protected]";
        public static string ServicePassword = "password";
    }

    static ClientContext GetContext()
    {
        var securePassword = new SecureString();
        foreach (char c in Configuration.ServicePassword)
        {
            securePassword.AppendChar(c);
        }

        var onlineCredentials = new SharePointOnlineCredentials(Configuration.ServiceUserName, securePassword);

        var context = new ClientContext(Configuration.ServiceSiteUrl);
        context.Credentials = onlineCredentials;

        return context;
    }

    static void GetLists()
    {
        var context = GetContext();
        var results = context.LoadQuery(context.Web.Lists.Include(list => list.Title, list => list.Id));
        context.ExecuteQuery();
        results.ToList().ForEach(x =>
        {
            Console.WriteLine("List: " + x.Title);
        });

        context.Dispose();
    }




    static void CreateProjectList()
    {
        ClientContext clientContext = GetContext();
        Web site = clientContext.Web;

        // Create the project list.
        ListCreationInformation listCreationInfo = new ListCreationInformation();
        listCreationInfo.Title = "Projects";
        listCreationInfo.TemplateType = (int)ListTemplateType.GenericList;
        List list = site.Lists.Add(listCreationInfo);

        // Add the category field to the list.
        Field catField = list.Fields.AddFieldAsXml(@"
            <Field Type='Choice' DisplayName='Category' Format='Dropdown'>
                <Default>IT</Default>
                <CHOICES>
                  <CHOICE>IT</CHOICE>
                  <CHOICE>Sales</CHOICE>
                  <CHOICE>Research and Development</CHOICE>
                  <CHOICE>CSR</CHOICE>
                </CHOICES>
            </Field>
            ", true, AddFieldOptions.DefaultValue);

        // Add list data.
        ListItemCreationInformation itemCreationInfo = new ListItemCreationInformation();
        Microsoft.SharePoint.Client.ListItem listItem = list.AddItem(itemCreationInfo);
        listItem["Title"] = "New public facing website";
        listItem["Category"] = "IT";
        listItem.Update();

        listItem = list.AddItem(itemCreationInfo);
        listItem["Title"] = "New Incident Management System";
        listItem["Category"] = "IT";
        listItem.Update();

        listItem = list.AddItem(itemCreationInfo);
        listItem["Title"] = "New internal sales strategy";
        listItem["Category"] = "Sales";
        listItem.Update();

        listItem = list.AddItem(itemCreationInfo);
        listItem["Title"] = "Youtube product visibility";
        listItem["Category"] = "CSR";
        listItem.Update();

        clientContext.ExecuteQuery();
    }
}

Answer 1

You can use Sharepoint client object model to access data from sharepoint:

SecureString password = new SecureString();

 foreach (char c in password)
 {
 password.AppendChar(c);
 }

            using (var context = new ClientContext(webUrl))
            {
                context.Credentials = new SharePointOnlineCredentials(userName,password);
                List announcementsList = context.Web.Lists.GetByTitle("Announcements"); 

ListItemCreationInformation itemCreateInfo = new ListItemCreationInformation(); 
ListItem newItem = announcementsList.AddItem(itemCreateInfo); 
newItem["Title"] = "My New Item!"; 
newItem["Body"] = "Hello World!"; 
newItem.Update(); 

context.ExecuteQuery();  
}