从Ruby中的哈希数组中删除哈希

Question

我有一系列哈希如下：

[{"k1"=>"v1", "k2"=>"75.1%"}, {"k1"=>"v2", "k2"=>"-NA-"}, {"k1"=>"v3", "k2"=>"5.1%"}]

现在，我想首先检查数组是否包含值为"k1"的键"v3"的哈希值。如果是，那么我想从数组中删除该哈希。

结果应为：

[{"k1"=>"v1", "k2"=>"75.1%"}, {"k1"=>"v2", "k2"=>"-NA-"}]

Answer 1

使用Array#delete_if：

arr = [{"k1"=>"v1", "k2"=>"75.1%"}, {"k1"=>"v2", "k2"=>"-NA-"}, {"k1"=>"v3", "k2"=>"5.1%"}]

arr.delete_if { |h| h["k1"] == "v3" }
#=> [{"k1"=>"v1", "k2"=>"75.1%"}, {"k1"=>"v2", "k2"=>"-NA-"}]

如果没有匹配条件的哈希，则数组保持不变。

Answer 2

您可以使用Array#reject执行此操作（如果您不想修改接收器）  以及Array#reject!（如果你想修改接收器）

arr = [{"k1"=>"v1", "k2"=>"75.1%"}, {"k1"=>"v2", "k2"=>"-NA-"}, {"k1"=>"v3", "k2"=>"5.1%"}]
p arr.reject { |h| h["k1"] == "v3" }
# >> [{"k1"=>"v1", "k2"=>"75.1%"}, {"k1"=>"v2", "k2"=>"-NA-"}]    

arr = [{"k1"=>"v1", "k2"=>"75.1%"}, {"k1"=>"v2", "k2"=>"-NA-"}, {"k1"=>"v3", "k2"=>"5.1%"}]
p arr.reject! { |h| h["k1"] == "v3" }
# >> [{"k1"=>"v1", "k2"=>"75.1%"}, {"k1"=>"v2", "k2"=>"-NA-"}]