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    <p>I've had to some something similar in the past. I went with the lambda approach because after compiling them I can cache them. I've removed the caching in this code.</p> <p>I included a few unit tests to show the usage of the method. I hope this is helpful.</p> <pre><code>private static object GetValueForPropertyOrField( object objectThatContainsPropertyName, IEnumerable&lt;string&gt; properties ) { foreach ( var property in properties ) { Type typeOfCurrentObject = objectThatContainsPropertyName.GetType(); var parameterExpression = Expression.Parameter( typeOfCurrentObject, "obj" ); Expression memberExpression = Expression.PropertyOrField( parameterExpression, property ); var expression = Expression.Lambda( Expression.GetDelegateType( typeOfCurrentObject, memberExpression.Type ), memberExpression, parameterExpression ).Compile(); objectThatContainsPropertyName = expression.DynamicInvoke( objectThatContainsPropertyName ); } return objectThatContainsPropertyName; } [TestMethod] public void TestOneProperty() { var dateTime = new DateTime(); var result = GetValueForPropertyOrField( dateTime, new[] { "Day" } ); Assert.AreEqual( dateTime.Day, result ); } [TestMethod] public void TestNestedProperties() { var dateTime = new DateTime(); var result = GetValueForPropertyOrField( dateTime, new[] { "Date", "Day" } ); Assert.AreEqual( dateTime.Date.Day, result ); } [TestMethod] public void TestDifferentNestedProperties() { var dateTime = new DateTime(); var result = GetValueForPropertyOrField( dateTime, new[] { "Date", "DayOfWeek" } ); Assert.AreEqual( dateTime.Date.DayOfWeek, result ); } </code></pre>
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    1. POLookup property in object graph via a string
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    1. USBrian Dishaw
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    1. COWhy is using a lambda a good idea vs. reflection?
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    2. COThe biggest reason is that Expressions utilize AST of the properties where reflection does not. The only faster way to do this would be to use Reflection.Emit and write it using IL, but that seems like it would be more trouble than it's worth. Please note that if you can cashe the delegate generated by the .Compile() step, it will help keep execution time low. You'll need to leverate the property as well as the type for the cache to retrieve your delegate that you want to invoke.
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    3. COI think this post might help further explain this as I'm not sure I did a good job. http://stackoverflow.com/questions/2697655/lambda-expression-based-reflection-vs-normal-reflection
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