objective-c - 字符串求值中的布尔公式

Question

我将公式存储1 && !0 && (0 || 1)在NSString变量中。我需要将此字符串评估为单个布尔值。有谁知道用于处理此或第 3 方解决方案的内置 obj-c 对象？

提前致谢。

Answer 1

我认为[NSPredicate parseWithFormat:]并且[NSPredicate evaluateWithObject:]可以在这里提供帮助。

Answer 2

Short of parsing it yourself, you won't be able to evaluate an expression like that in Objective-C during runtime since it is not an interpreted language.

Here are just a few (of many) other resources that pretty much echo this:

• eval in Objective-C
• Is there something like Matlab's eval statement in Objective-C 2.0?
• “eval” for Objective-C code

This post may get you a step closer to what you are trying to achieve. In any scenario, you will have to parse it yourself.