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POlambda Expression as a property
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  1. POlambda Expression as a property
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    copied!<p>I have a working setup which is not strongly typed and relies on reflection.</p> <p>I have a class, say</p> <pre><code>class Person{ public string FirstName {get ; set;} public string LastName {get; set;} public int Age {get; set;} ... // some more public properties } </code></pre> <p>and </p> <pre><code>class CellInfo { public string Title {get; set;} public string FormatString {get; set;} } </code></pre> <p>and I have a dictionary like this</p> <pre><code>Dictionary&lt;string, CellInfo&gt; fields = new Dictionary&lt;string, CellInfo&gt;(); fields.Add("FirstName", new CellInfo {Title = "First Name", FormatString = "Foo"}); fields.Add("LastName", new CellInfo {Title = "Last Name", FormatString = "Bar"}); </code></pre> <p>It's a simple dictionary with property Names and some info about them. I pass the dictionary to another module that processes Person instances and I do</p> <pre><code>Dictionary&lt;string, CellInfo&gt; fields = SomeMethodToGetDictionary(); foreach(Person p in someCollection) { foreach(var field in fields) { object cellValue = type(Person).GetProperty(field.Key).GetValue(p, null); // use cellValue and info on field from field.Value somewhere. ... } } </code></pre> <p>This method of passing the string for field name and using reflection works, but I was wondering if there is a strongly-typed method of doing this.</p> <p>What I had in mind was having a property that stored a linq expression, something like this </p> <pre><code>fields.Add("FirstName", new CellInfo { Title = "First Name", FormatString = "Foo", EvalExpression = p =&gt; p.FirstName }); </code></pre> <p>and during usage, somehow use the <code>EvalExpression</code> on a person object and get the property value. I have no clue where to begin or what the syntax would be like to have a property like this that's evaluateable. I'm new to function delegates and expression trees that I don't even know the right keywords to search for. Hope my description is clear; if not, let me know and I'll details as necessary. Any assistance would much appreciated.</p>
 

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