红宝石 |数组 keep_if()函数

Array#keep_if() ：keep_if()是一个 Array 类方法，它返回满足给定条件的数组元素。

Syntax: Array.keep_if()

Parameter: Array

Return: the array element that satisfy the given condition.

示例 #1：

# Ruby code for keep_if() method
  
# declaring array
a = [18, 22, 33, 3, 5, 6]
  
# declaring array
b = [1, 4, 1, 1, 88, 9]
  
# declaring array
c = [18, 22, 3, 3, 50, 6]
  
# keep_if
puts "keep_if method : #{a.keep_if {|num| num > 10 }}\n\n"
  
# keep_if
puts "keep_if method : #{b.keep_if {|x| x.odd? }}\n\n"

输出 ：

keep_if method : [18, 22, 33]

keep_if method : [1, 1, 1, 9]

示例 #2：

# Ruby code for keep_if() method
  
# declaring array
a = [18, 22, 33, 3, 5, 6]
  
# declaring array
b = [1, 4, 1, 1, 88, 9]
  
# declaring array
c = [18, 22, 3, 3, 53, 6]
  
# keep_if
puts "keep_if method : #{c.keep_if {|num| num > 10 }}\n\n"
  
# keep_if
puts "keep_if method : #{c.keep_if {|num| num.even? }}\n\n"

输出 ：

keep_if method : [18, 22, 53]

keep_if method : [18, 22]