红宝石 |哈希键()函数
Hash#key()是一个 Hash 类方法,它给出了键值对应的值。如果值不存在,则返回 nil。
Syntax: Hash.key()
Parameter: Hash values
Return: key corresponding to the value
nil – If value doesn’t exist
示例 #1:
# Ruby code for Hash.key() method
# declaring Hash value
a = {a:100, b:200}
# declaring Hash value
b = {a:100, c:300, b:200}
# declaring Hash value
c = {a:100}
# key Value
puts "Hash a key form : #{a.key(200)}\n\n"
puts "Hash b key form : #{b.key(100)}\n\n"
puts "Hash c key form : #{c.key(200)}\n\n"
输出 :
Hash a key form : b
Hash b key form : a
Hash c key form :
示例 #2:
# Ruby code for Hash.key() method
# declaring Hash value
a = { "a" => 100, "b" => 200 }
# declaring Hash value
b = {"a" => 100}
# declaring Hash value
c = {"a" => 100, "c" => 300, "b" => 200}
# key Value
puts "Hash a key form : #{a.key(200)}\n\n"
puts "Hash b key form : #{b.key(100)}\n\n"
puts "Hash c key form : #{c.key(200)}\n\n"
输出 :
Hash a key form : b
Hash b key form : a
Hash c key form : b