cbegin()/ cend()vs constBegin()/ constEnd()

Question

Qt 5.0引入了迭代器方法,cbegin()并引入了cend()不同的容器类,如QList或QMap.

但是这些课程中也有方法constBegin()和constEnd()方法.

所有这些方法都是constSTL风格的const_iterator.

• 难道cbegin()/ cend()比相同的功能constBegin()/ constEnd()？对我来说似乎是这样,但在QList,QMap或容器类的文档中没有说明任何内容.
• 是否有人应该使用cbegin()/ cend()而不是constBegin()/ constEnd()反之亦然？

Answer 1

cbegin() and cend() where introduced for compatibility with Standard Library containers, which all contain such functions since C++11.
Qt just wants to keep it interface similar to the standard library. constBegin() etc. are just older versions (Qt added them before C++11 was released). There is no difference in using them.

我会使用constBegin(),constEnd()因为它们更明确和'Qt风格',但这只是我个人的偏好.cbegin()/ cend()可能被一些为标准容器实现的算法使用(因此它们存在于Qt中 - 它们有助于重用一些代码).如果您希望在某些时候想要在Qt之外重用代码,请使用它们.