// Find the default embedded space:
ISpaceProxy proxy = GigaSpacesFactory.FindSpace("/./MySpace");
// Create an automatically disposed transaction scope:
using (ITransaction tx = proxy.CreateLocalTransaction())
{
    try
    {
        // Read a person - use the transaction to lock it:
        Person p = proxy.Take<Person>(new Person(), tx);
        // Update the person's name:
        p.Name = p.Name + " (updated in a transaction)";
        // Update the person in space:
        proxy.Write<Person>(p, tx);
        // Commit the transaction:
        tx.Commit();
    }
    catch
    {
        // In case of an exception, abort the transaction:
        tx.Abort();
        throw;
    }
}