如何从std::exception中获取原始异常？

#include <iostream>
#include <exception>

class MyException : public std::exception {
public:
    MyException(const std::exception& originalException) : originalException(originalException) {}

    const char* what() const noexcept override {
        return originalException.what();
    }

private:
    const std::exception& originalException;
};

int main() {
    try {
        // 假设这里发生了某个异常
        throw std::runtime_error("发生了一个错误");
    }
    catch (const std::exception& ex) {
        try {
            // 使用自定义派生类包装原始异常
            throw MyException(ex);
        }
        catch (const std::exception& myEx) {
            std::cout << "捕获到自定义异常： " << myEx.what() << std::endl;
        }
    }
    return 0;
}