Ruby Hash select!()方法

Hash#select!()是一个Hash类方法，它根据区块条件检查哈希中的数组是否存在。

语法。Hash.select!()

参数：哈希值

区块条件

返回：根据区块条件，哈希中的数组是存在的，否则返回false。

例子 #1 :

# Ruby code for Hash.select!() 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}
  
  
# select! Value
puts "Hash a select! form : #{a.select! {|key, value| key < "b"}}\n\n"

输出:

Hash a select! form : {"a"=>100}

例子 #2 :

# Ruby code for Hash.select!() method
  
# declaring Hash value
b = {"a" => 100}
  
# declaring Hash value
c = {"a" => 100, "c" => 300, "b" => 200}
  
  
# select! Value
  
puts "Hash b select! form : #{b.select!{|key, value| value < 200}}\n\n"
  
puts "Hash c select! form : #{c.select!{|key, value| key < "b"}}\n\n"

输出:

Hash b select! form : 

Hash c select! form : {"a"=>100}