c# - 如何获得表达结果？

Question

我构建了一个如下所示的表达式:

Expression left = Expression.Constant(5, typeof(int));
Expression right = Expression.Constant(6, typeof(int));
Expression result = Expression.Add(left,right);

那么，能否通过表达式结果得到“5+6”的真实结果呢？

Answer 1

我认为您需要将其编译为 Func:

Expression left = Expression.Constant(5, typeof(int));
Expression right = Expression.Constant(6, typeof(int));
Expression result = Expression.Add(left,right);

var compiled = Expression.Lambda<Func<int>>(result).Compile();
Console.WriteLine(compiled.Invoke());

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