ruby使用if-inside循环和用户输入

我试图使循环通过if语句，若用户输入无效，它会一直告诉输入数字，若为真，则中断

我试过了这是我的密码

class String
  def numeric?
    Float(self) != nil rescue false
  end
end
cond = false

puts "Enter number "
line = gets.chomp.strip

 while cond == false
    if (line.numeric?  )
        puts "Ok nice  "
        cond = true
        else 
        puts "Please enter number only  "

    end
 end

但如果条件为假，只需打印“请仅输入数字”即可继续循环

我很乐意接受任何建议

谢谢

试试这个：

 while cond == false
    if (line.numeric?  )
        puts "Ok nice  "
        cond = true
    else 
        puts "Please enter number only  "
        line = gets.chomp.strip
    end     
 end

while true                                                                                                                                                                                                             
  print "Enter number "                                                                                                                                                                                           
  line = gets.chomp.strip

  if line.numeric?
    puts "Ok nice"
    break
  else
    puts "Please enter number only"
  end                                                                                                                                                                                        
end

---

问题是，在告诉用户只需输入一个数字后，您不会读取另一个数字，您只需返回

解决此问题的最简单方法是将提示符和输入移动到

while

循环中，有点像这样：

class String
  def numeric?
    Float(self) != nil rescue false
  end
end
cond = false

 while cond == false
    puts "Enter number "
    line = gets.chomp.strip

    if (line.numeric?  )
        puts "Ok nice  "
        cond = true
     else 
        puts "Please enter number only  "
    end
 end

---

在重写String方法之后，请立即尝试以下操作：

while true                                                                                                                                                                                                             
  print "Enter number "                                                                                                                                                                                           
  line = gets.chomp.strip

  if line.numeric?
    puts "Ok nice"
    break
  else
    puts "Please enter number only"
  end                                                                                                                                                                                        
end

---

你不需要再打电话了。