Ruby:使用特定值删除散列中的所有键值对

Question

我的哈希:

hash={value1: "2",value2: "1",value3: "6",value4: "2" }  

我想要的是删除值为"2"的所有键值对,如下所示:

hash={value2: "1",value3: "6"}   

怎么做？

Answer 1

这是怎么用的delete_if ？

hash={value1: "2",value2: "1",value3: "6",value4: "2" } 
hash.delete_if{|_,v| v == "2"}
# => {:value2=>"1", :value3=>"6"}
hash
# => {:value2=>"1", :value3=>"6"}

如果您不想修改原件,hash那么您也可以使用Hash#reject:

hash={value1: "2",value2: "1",value3: "6",value4: "2" } 
new_hash=hash.reject{|_,v| v == "2"}
# => {:value2=>"1", :value3=>"6"}
hash # => {:value1=>"2", :value2=>"1", :value3=>"6", :value4=>"2"}