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copied!<p>A page of code is a thousand words, so here's how Microsoft does it in <a href="http://compositewpf.codeplex.com/" rel="nofollow">Prism</a>:</p> <pre><code>///<summary> /// Provides support for extracting property information based on a property expression. ///</summary> public static class PropertySupport { /// <summary> /// Extracts the property name from a property expression. /// </summary> /// <typeparam name="T">The object type containing the property specified in the expression.</typeparam> /// <param name="propertyExpression">The property expression (e.g. p => p.PropertyName)</param> /// <returns>The name of the property.</returns> /// <exception cref="ArgumentNullException">Thrown if the <paramref name="propertyExpression"/> is null.</exception> /// <exception cref="ArgumentException">Thrown when the expression is:<br/> /// Not a <see cref="MemberExpression"/><br/> /// The <see cref="MemberExpression"/> does not represent a property.<br/> /// Or, the property is static. /// </exception> public static string ExtractPropertyName<T>(Expression<Func<T>> propertyExpression) { if (propertyExpression == null) { throw new ArgumentNullException("propertyExpression"); } var memberExpression = propertyExpression.Body as MemberExpression; if (memberExpression == null) { throw new ArgumentException(Resources.PropertySupport_NotMemberAccessExpression_Exception, "propertyExpression"); } var property = memberExpression.Member as PropertyInfo; if (property == null) { throw new ArgumentException(Resources.PropertySupport_ExpressionNotProperty_Exception, "propertyExpression"); } var getMethod = property.GetGetMethod(true); if (getMethod.IsStatic) { throw new ArgumentException(Resources.PropertySupport_StaticExpression_Exception, "propertyExpression"); } return memberExpression.Member.Name; } } </code></pre> <p>If you want to take attributes into account it's going to be slightly more complicated, but the general idea of accepting an <code>Expression<Func<T>></code> and fishing out the name of the property being targeted is the same.</p> <p><strong>Update:</strong> As is, the method will accept only one parameter; I only provided it as a guideline. The idea can be generalized of course:</p> <pre><code>public static string[] ExtractPropertyNames<T>( Expression<Func<T, object>> propertyExpression) </code></pre> <p>This method will accept an expression that takes a T and returns an anonymous type which you can then reflect upon. You could substitute a second type parameter for <code>object</code> but that doesn't really do anything here because the only thing you want to do is reflect on the type.</p>

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