代碼如下：

#pragma mark - xcode注釋標(biāo)記(頂部有線)

// MARK: - A section heading or a comment with a separator line above
// TODO: - A to-do item with a separator line above
// FIXME: - A bug fix reminder with a separator line above
// !!!: - A red flag with separator line above
// ???: - A question with a separator line above

#pragma mark - xcode注釋標(biāo)記（底部有線）

// MARK: A section heading or a comment with a separator line below -
// TODO: A to-do item with a separator line below -
// FIXME: A bug fix reminder with a separator line below -
// !!!: A red flag with a separator line below -
// ???: A question with a separator line below -

#pragma mark - xcode注釋標(biāo)記（頂部和底部都有線）

// MARK: - A section heading or a comment with a separator line below -
// TODO: - A to-do item with a separator line below -
// FIXME: - A bug fix reminder with a separator line below -
// !!!: - A red flag with a separator line below -
// ???: - A question with a separator line below -

效果圖如下：

Xcode Dark

Xcode Light