4.4 移除控制标记

【1】原代码

// 重构前
QString foundPerson(QStringList people)
{
    QString found = QString();
    for (int i = 0; i < people.size(); ++i)
    {
        if (people[i].compare("Don") == 0)
        {
            found = "Don";
        }

        if (people[i].compare("John") == 0)
        {
            found = "John";
        }

        if (people[i].compare("Dave") == 0)
        {
            found = "Dave";
        }
    }

    return found;
}

【2】移除控制标记

// 重构后
QString foundPerson(QStringList people)
{
    QStringList candidates = {"Don", "John", "Dave"};
    for (int i = 0; i < people.size(); ++i)
    {
        if (candidates.contains(people[i]))
        {
            return people[i];
        }
    }

    return QString();
}

【3】总结

在一系列布尔表达式中，某个变量带有“控制标记”（control flag）的作用。以break语句或return语句取代控制标记。

 

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