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POLambda Generic Expression w/ Out Parameter
 

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    <p>I am trying to use expressions w/ lambda delegates to obtain the name of the calling method but it is not formatting it properly. </p> <p>Here is what I have so far: Question is.. how do I get what I am to expect similar to foo.Method.Name for both lambda and regular methods?</p> <p>So far, I have tried with and without expressions.. and get the same results.<br></p> <blockquote> <p>&lt; HandleAddedDevice >b__2d</p> </blockquote> <pre><code> // ************************************************************************** public delegate TResult TimerDelegateOut &lt;T, out TResult&gt;(out T foo); // ************************************************************************** public static string GetName&lt;T&gt;(this Expression&lt;T&gt; expression) { var callExpression = expression.Body as MethodCallExpression; return callExpression != null ? callExpression.Method.Name : string.Empty; } // ************************************************************************** public static Expression&lt;TimerDelegateOut&lt;T, TResult&gt;&gt; ToExpression&lt;T, TResult&gt;(this TimerDelegateOut&lt;T, TResult&gt; call) { var p1 = Expression.Parameter(typeof(T).MakeByRefType(), "value"); MethodCallExpression methodCall = call.Target == null ? Expression.Call(call.Method, p1) : Expression.Call(Expression.Constant(call.Target), call.Method, p1); return Expression.Lambda&lt;TimerDelegateOut&lt;T, TResult&gt;&gt;(methodCall, p1); } // ************************************************************************** public static Expression&lt;Func&lt;TResult&gt;&gt; ToExpression&lt;TResult&gt;(this Func&lt;TResult&gt; call) { MethodCallExpression methodCall = call.Target == null ? Expression.Call(call.Method) : Expression.Call(Expression.Constant(call.Target), call.Method); return Expression.Lambda&lt;Func&lt;TResult&gt;&gt;(methodCall); } // ************************************************************************** public static TResult TimeFunction&lt;T, TResult&gt;(TimerDelegateOut&lt;T, TResult&gt; foo, out T bar) { try { var result = foo.ToExpression().Compile().Invoke(out bar); Console.WriteLine(foo.GetName()); // is OKAY return result; } catch (Exception) { bar = default(T); return default(TResult); } } // ************************************************************************** public static TResult TimeFunction&lt;TResult&gt;(Func&lt;TResult&gt; foo) { try { var result = foo.ToExpression().Compile().Invoke(); Console.WriteLine(foo.GetName()); // &lt;-- prints "foo" ??? Not correct. return result; } catch (Exception) { bar = default(T); return default(TResult); } } ------------- Result GetCamera_HWInfo(out Cam_HWInfo obj) { obj = new Cam_HWInfo() { &lt; fill container here &gt; }; return Result.cmrOk; } //------------ private void HandleAddedDevice() { ... Cam_HWInfo camHWInfo; Result result = Watchdog.TimeFunction(GetCamera_HWInfo, out camHWInfo); ... // Try this one.. I am also using. var connect = new Func&lt;bool&gt;(delegate { try { // ... } catch (Exception ex) { return false; } return true; }); result = Watchdog.TimeFunction(connect); } //------------ // Assume OEP static void Main(string[] args) { HandleAddedDevice(); } </code></pre> <hr> <p>Here is a test driver I can show in a simple case of what I would expect. The 3x methods I need to support are:</p> <ol> <li><code>Func&lt;T, TR&gt;()</code></li> <li><code>Func&lt;T, TR&gt;(T foo)</code></li> <li><code>Func&lt;T, TR&gt;(out T foo)</code></li> </ol> <p><strong>Example:</strong> Lambda expressions are nameless. It will show up something like &lt; No Name>. </p> <p>.Method.Name is correct, but since it is a sub-method of its Parent within the calling scope, it actually is registered on the stack, as follows:</p> <p>&lt; HandleAddedDevice >b__2d</p> <p>I read <a href="https://stackoverflow.com/questions/1495465/get-name-of-action-func-delegate">here</a> that I might need to make it an expression and then Expression.Compile() to convert it to an Action (or in my case Func)?</p> <p>They said it may not be possible without a compiled expression <a href="https://stackoverflow.com/questions/767733/converting-a-net-funct-to-a-net-expressionfunct">here</a>... Maybe this will help you to explain to me where my code is a bit off in what I am trying to do. </p> <pre><code> class Program { public static class ReflectionUtility { public static string GetPropertyName&lt;T&gt;(Expression&lt;Func&lt;T&gt;&gt; expression) { MemberExpression body = (MemberExpression) expression.Body; return body.Member.Name; } } static void Main(string[] args) { Func&lt;int, bool&gt; lambda = i =&gt; i &lt; 5; Func&lt;int, bool&gt; del = delegate(int i) { return i &lt; 5; }; // Create similar expression #1. Expression&lt;Func&lt;int, bool&gt;&gt; expr1 = i =&gt; i &lt; 5; // Compile the expression tree into executable code. Func&lt;int, bool&gt; exprC1 = expr1.Compile(); // Invoke the method and print the output. Console.WriteLine("lambda(4) = {0} : {1} ", lambda(4), lambda.Method.Name); Console.WriteLine("del (4) = {0} : {1} ", del(4), del.Method.Name); Console.WriteLine("expr1 (4) = {0} : {1} ", exprC1(4), exprC1.Method.Name); Console.WriteLine(" = {0}", ReflectionUtility.GetPropertyName(() =&gt; lambda)); Console.WriteLine(" = {0}", ReflectionUtility.GetPropertyName(() =&gt; del)); Console.Write("Press any key to continue..."); Console.ReadKey(); } </code></pre> <h2> <strong>OUTPUT</strong></h2> <pre><code>lambda(4) = True : &lt;Main&gt;b__0 del (4) = True : &lt;Main&gt;b__1 expr1 (4) = True : lambda_method = lambda = del Press any key to continue... </code></pre>
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    2. COThe container out I am trying to fill. Refresh the page.. I updated the question. As you can see I traced it to the method where it invokes the call and throws an exception. Seems to persist in the extension ToExpression... I can try.catch something in there to see if I get more info, but it wouldnt matter since I am catching it up one frame. The whole point is to get the name of the method for both lambda / delegates inline and normal methods using foo.GetName();
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