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    <p>You could of course walk the expression-tree and then use <code>Delegate.CreateDelegate</code> to create the appropriate <code>Action&lt;,&gt;</code>. It's quite simple, except for all of the validation-checks (I'm unsure if I've covered everything):</p> <p><s>I'm no expression-tree expert, but I don't <em>think</em> building an expression-tree and then calling <code>Compile</code> is possible here since expression-trees can't contain assignment statements, as far as I know.</s> (<strong>EDIT</strong>: Apparently, these have been added in .NET 4. It's a hard-to-find feature since the C# compiler doesn't seem to be able to build them from lambdas).</p> <pre><code>public static Action&lt;TContaining, TProperty&gt; CreateSetter&lt;TContaining, TProperty&gt; (Expression&lt;Func&lt;TContaining, TProperty&gt;&gt; getter) { if (getter == null) throw new ArgumentNullException("getter"); var memberEx = getter.Body as MemberExpression; if (memberEx == null) throw new ArgumentException("Body is not a member-expression."); var property = memberEx.Member as PropertyInfo; if (property == null) throw new ArgumentException("Member is not a property."); if(!property.CanWrite) throw new ArgumentException("Property is not writable."); return (Action&lt;TContaining, TProperty&gt;) Delegate.CreateDelegate(typeof(Action&lt;TContaining, TProperty&gt;), property.GetSetMethod()); } </code></pre> <p><strong>Usage</strong>:</p> <pre><code>public class Person { public int Age { get; set; } } ... static void Main(string[] args) { var setter = CreateSetter((Person p) =&gt; p.Age); var person = new Person(); setter(person, 25); Console.WriteLine(person.Age); // 25 } </code></pre> <p>Do note that this creates an <em>open</em> instance delegate, meaning that it's not bound to any particular instance of <code>TContaining</code>. It's simple to modify it to be bound to a <em>specific</em> instance; you'll have to pass a <code>TContaining</code> as well to the method and then use a different overload of <code>Delegate.CreateDelegate</code>. The signature of the method would then look something like:</p> <pre><code>public static Action&lt;TProperty&gt; CreateSetter&lt;TContaining, TProperty&gt; (Expression&lt;Func&lt;TContaining, TProperty&gt;&gt; getter, TContaining obj) </code></pre>
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    1. POCreate an Action<T> to "set" a property, when I am provided with the LINQ Expression for the "get"
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    1. CONot sure, but I think they added assignments in .net 4. But the setter should already have the correct signature, so it's not necessary.
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    2. COYes, assignment is in 4.0 - but you really don't need it here; Delegate.CreateDelegate is ideal. +1
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    3. CO@CodeInChaos, @Marc Gravell: Thanks, that was news to me.
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