我需要像这样翻译字符串:
"DateTime.Now.AddDays(-7)"
转换成它们的等效表达式。
我只对 DateTime 类感兴趣。 .Net 中是否有任何内置功能可以帮助我执行此操作，还是我只需要编写自己的小解析器？
最佳答案
您可以雇用 FLEE为你做表达式解析。下面的代码在 Silverlight 中经过测试和工作(我相信完整的 C#，它在创建表达式方面可能有稍微不同的语法，但无论如何它可能完全像这样工作)
ExpressionContext context = new ExpressionContext();
//Tell FLEE to expect a DateTime result; if the expression evaluates otherwise,
//throws an ExpressionCompileException when compiling the expression
context.Options.ResultType = typeof(DateTime);
//Instruct FLEE to expose the `DateTime` static members and have
//them accessible via "DateTime".
//This mimics the same exact C# syntax to access `DateTime.Now`
context.Imports.AddType(typeof(DateTime), "DateTime");
//Parse the expression, naturally the string would come from your data source
IDynamicExpression expression = ExpressionFactory.CreateDynamic("DateTime.Now.AddDays(-7)", context);
//I believe there's a syntax in full C# that lets you evaluate this
//with a generic flag, but in this build, I only have it return type
//`Object` so we cast (it does return a `DateTime` though)
DateTime date = (DateTime)expression.Evaluate();
Console.WriteLine(date); //January 25th (7 days ago for me!)
关于c# - 解析 "DateTime.Now"？，我们在Stack Overflow上找到一个类似的问题： https://stackoverflow.com/questions/14647703/