Ruby Hash each_key用法及代码示例

Hash＃each_key()是一种Hash类方法，该方法通过将键作为参数传递来找到对哈希中的each_key对调用一次块的嵌套值。

用法：Hash.each_key()

参数：散列值

返回：为哈希中的key_value对调用一次块，并使用key作为参数；否则，如果未传递任何参数，则为Enumerator。

示例1:

# Ruby code for Hash.each_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} 
  
# each Value 
puts "Hash a each_key form : #{a.each_key()}\n\n"
  
puts "Hash b each_key form : #{b.each_key {|key| puts "#{key}"}}\n\n"
  
puts "Hash c each_key form : #{c.each_key {|value| puts "#{value}"}}\n\n"

输出：

Hash a each_key form : #

a
c
b
Hash b each_key form : {:a=>100, :c=>300, :b=>200}

a
Hash c each_key form : {:a=>100}

示例2:

# Ruby code for Hash.each_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} 
  
# each Value 
puts "Hash a each_key form : #{a.each_key()}\n\n"
  
puts "Hash b each_key form : #{b.each_key {|key| puts "#{key}"}}\n\n"
  
puts "Hash c each_key form : #{c.each_key {|value| puts "#{value}"}}\n\n"

输出：

Hash a each_key form : #

a
Hash b each_key form : {"a"=>100}

a
c
b
Hash c each_key form : {"a"=>100, "c"=>300, "b"=>200}

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注：本文由纯净天空筛选整理自Kirti_Mangal大神的英文原创作品 Ruby | Hash each_key function。非经特殊声明，原始代码版权归原作者所有，本译文未经允许或授权，请勿转载或复制。