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?
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?