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copied!<p><strong>How to get the database column / field names and class property names for an entity mapped by NHibernate:</strong></p> <pre><code>using System; using System.Collections.Generic; using System.Reflection; using NHibernate; using NHibernate.Persister.Entity; namespace Stackoverflow.Example { /// <summary> /// NHibernate helper class /// </summary> /// <remarks> /// Assumes you are using NHibernate version 3.1.0.4000 or greater (Not tested on previous versions) /// </remarks> public class NHibernateHelper { /// <summary> /// Creates a dictionary of property and database column/field name given an /// NHibernate mapped entity /// </summary> /// <remarks> /// This method uses reflection to obtain an NHibernate internal private dictionary. /// This is the easiest method I know that will also work with entitys that have mapped components. /// </remarks> /// <param name="sessionFactory">NHibernate SessionFactory</param> /// <param name="entity">An mapped entity</param> /// <returns>Entity Property/Database column dictionary</returns> public static Dictionary<string, string> GetPropertyAndColumnNames(ISessionFactory sessionFactory, object entity) { // Get the objects type Type type = entity.GetType(); // Get the entity's NHibernate metadata var metaData = sessionFactory.GetClassMetadata(type.ToString()); // Gets the entity's persister var persister = (AbstractEntityPersister)metaData; // Creating our own Dictionary<Entity property name, Database column/filed name>() var d = new Dictionary<string, string>(); // Get the entity's identifier string entityIdentifier = metaData.IdentifierPropertyName; // Get the database identifier // Note: We are only getting the first key column. // Adjust this code to your needs if you are using composite keys! string databaseIdentifier = persister.KeyColumnNames[0]; // Adding the identifier as the first entry d.Add(entityIdentifier, databaseIdentifier); // Using reflection to get a private field on the AbstractEntityPersister class var fieldInfo = typeof(AbstractEntityPersister) .GetField("subclassPropertyColumnNames", BindingFlags.NonPublic | BindingFlags.Instance); // This internal NHibernate dictionary contains the entity property name as a key and // database column/field name as the value var pairs = (Dictionary<string, string[]>)fieldInfo.GetValue(persister); foreach (var pair in pairs) { if (pair.Value.Length > 0) { // The database identifier typically appears more than once in the NHibernate dictionary // so we are just filtering it out since we have already added it to our own dictionary if (pair.Value[0] == databaseIdentifier) break; d.Add(pair.Key, pair.Value[0]); } } return d; } } } </code></pre> <p>Usage:</p> <pre><code>// Get your NHiberate SessionFactory wherever that is in your application var sessionFactory = NHibernateHelper.SessionFactory; // Get an entity that you know is mapped by NHibernate var customer = new Customer(); // Get a dictionary of the database column / field names and their corresponding entity property names var propertyAndColumnNamesDictionary = Stackoverflow.Example.NHibernateHelper.GetPropertyAndColumnNames(sessionFactory, customer); </code></pre>

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