我有下面的数组

cities = ["Kathmandu", "Pokhara", "", "Dharan", "Butwal"]

我想从数组中删除空白元素,并希望得到以下结果:

cities = ["Kathmandu", "Pokhara", "Dharan", "Butwal"]

有没有像compact这样不需要循环的方法?


当前回答

在我的项目中,我使用delete:

cities.delete("")

其他回答

使用严格的join & split更新

cities = ["Kathmandu", "Pokhara", "", "Dharan", "Butwal"]
cities.join(' ').split

结果将是:

["Kathmandu", "Pokhara", "Dharan", "Butwal"]

注意:这对有空间的城市不起作用

这里还有一种方法可以实现这一点

我们可以使用presence和select

cities = ["Kathmandu", "Pokhara", "", "Dharan", nil, "Butwal"]

cities.select(&:presence)

["Kathmandu", "Pokhara", "Dharan", "Butwal"]

删除空值:

 ['a', nil, 'b'].compact  ## o/p =>  ["a", "b"]

删除空字符串:

   ['a', 'b', ''].select{ |a| !a.empty? } ## o/p => ["a", "b"]

删除空字符串和空字符串:

['a', nil, 'b', ''].select{ |a| a.present? }  ## o/p => ["a", "b"]

如果你的数组中有混合类型,下面是一个解决方案:

[nil,"some string here","",4,3,2]

解决方案:

[nil,"some string here","",4,3,2].compact.reject{|r| r.empty? if r.class == String}

输出:

=> ["some string here", 4, 3, 2]
cities.reject! { |c| c.blank? }

为什么要用空白?在空的吗?blank可以识别nil,空字符串和空白。例如:

cities = ["Kathmandu", "Pokhara", " ", nil, "", "Dharan", "Butwal"].reject { |c| c.blank? }

仍然会返回:

["Kathmandu", "Pokhara", "Dharan", "Butwal"]

叫空?On " "将返回false,您可能希望它为true。

注:空白?只能通过Rails访问,Ruby只支持空?