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我想像这样打印数组 -

Arr= ["abcd","1223","  10829380","pqrs"]

Answer 1

您应该遵循命名模式，而不是使用Arr，因为这通常是使用的对于班级名称。

arr = ["abcd","1223"," 10829380","pqrs"]
whitespace_removed_arr = arr.map { |item| item.strip }

map迭代字符串数组（arr）并构建一个包含块返回值的新数组。

如果您愿意，可以使用较短的版本：

arr = ["abcd","1223"," 10829380","pqrs"]
whitespace_removed_arr = arr.map(&:strip)

请注意，提出strip!和map（iof strip的原位版本）的解决方案很可能在strip!之后无法正常工作或工作（奇怪的是））当字符串未更改时返回nil。

"".strip => ""
"".strip! => nil
"".strip => ""
" ".strip! => ""

如果您想使用条带的inplace变体并修改原始数组，则需要使用each

arr.each(&:strip!)

each会丢弃该块的返回值，而strip!会修改该字符串。

Answer 2

您可以使用Array#map!或Array.map。 Array#map!更改原始数组，Array#map返回一个新数组，以便原始数组保持不变。 map函数迭代数组并为数组中的每个元素执行给定的块。

arr = ["abcd", "1223", " 10829380", "pqrs"]
arr.map!{ |el| el.strip }
arr
# => ["abcd", "1223", "10829380", "pqrs"]

# or

arr = ["abcd", "1223", " 10829380", "pqrs"]
arr.map{ |el| el.strip }
# => ["abcd", "1223", "10829380", "pqrs"]
arr
# => ["abcd", "1223", " 10829380", "pqrs"]

Btw：ruby中的变量以小写字母或_（arr）开头。

如何使用Ruby从数组中删除空格

2 个答案: