扭转前pression＆LT; Func键＆LT; T，TResult＆GT;＆GT; .Compile（）？ [英] Reverse of Expression<Func<T,TResult>>.Compile()?

问题描述

因为我们可以：

Expression<Func<int, bool>> predicate = x => x > 5;
var result = Enumerable.Range(0,10).Where(predicate.Compile());

如何：

Func<int,bool> predicate = x => x > 5;
Expression<Func<int,bool>> exp = predicate.Decompile();

这就是我想要得到相应的防爆pression的的 Func键。这可能吗？

That is, I want to get the corresponding Expression of the Func. Is it possible?

推荐答案

有没有神奇的反编译（）的代表的情况下，短的解构IL（也许Mono.Cecil能做到）。如果你想要一个EX pression树，你得的启动的和前pression树，所以有防爆pression＆LT; Func键＆LT; INT ，布尔＆GT;＆GT; througout

There is no magic Decompile() for a delegate instance, short of deconstructing the IL (perhaps with mono.cecil). If you want an expression tree, you'll have to start with an expression tree, so have Expression<Func<int, bool>> througout.

作为一个边缘的情况下，你可以得到的基本的距离的方法委托信息的委托的。方法（即 MethodInfo的）和 .TARGET （即为arg0 ） - 然而，对于涉及拉姆达大多数情况下，或匿名方法，这将指向上采集类的编译器生成的方法，所以不会真正帮助你多少。这是pretty的多局限于场景，如：

As an edge case, you can get basic method delegate information from the delegate's .Method (the MethodInfo) and .Target (the arg0) - however, for most scenarios involving a lambda or anonymous method this will point at the compiler-generate method on the capture class, so won't really help you much. It is pretty much limited to scenarios like:

Func<string,int> parse = int.Parse;

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