how to know Array if have key?

[Zhenning Guan]

a_array= [{"1"=>"11"}, {"2"=>"22"}]
how to test if a_array have a key "11"????

 

[Clifford Heath]

a_array= [{"1"=>"11"}, {"2"=>"22"}]
how to test if a_array have a key "11"????

Arrays don't have keys, Hashes do.
Here, you have an array with two elements.
Both the elements are hashes. Neither hash has
the key "11", though the first has it as a value.

If you want to know whether a hash has a value,
it's slow; you have to search the hash, or extract
all the values and check for the one you care about.

 

[Chris Howe]

[Note: parts of this message were removed to make it a legal post.]

If you have a hash and you want to find whether or not a given value exists
as a key you can use the "has_key?" method

h = { "a" => 100, "b" => 200 }
h.has_key?("a") #=> true
h.has_key?("z") #=> false

 

[Zhenning Guan]

thank you for help. clear.