Question

以下代码生成错误，我看不到问题。有人可以帮忙吗？

customer_array = [‘Ken’,’William’,’Catherine’,’Mark’,’Steve’,’Sam’]
customer_hash = {
‘Ken’ => ‘Fiction’,
‘William’ => ‘Mystery’,
‘Catherine’ => ‘Computer’,
‘Mark’ => ‘Fiction’,
‘Steve’ => ‘Sports’,
‘Sam’ => ‘Fiction’
}
# => customer_array.rb:6: syntax error, unexpected tSTRING_BEG , expecting '}'
# 'William' => 'Mystery'
#      ^

Answer 1

问题似乎与那些奇怪的背引言有关。试试这个：

customer_array = ["Ken","William","Catherine","Mark","Steve","Sam"]
customer_hash = {
    "Ken" => "Fiction",
    "William" => "Mystery",
    "Catherine" => "Computer",
    "Mark" => "Fiction",
    "Steve" => "Sports",
    "Sam" => "Fiction"
}

Answer 2

你的引号是非ASCII字符。

将其替换为ASCII '或"。

或将# encoding: UTF-8添加到文件的开头并将其包装成ASCII引号，如下所示：

# encoding: UTF-8

customer_hash = {
  "‘Ken’" => "‘Fiction’",
}

Answer 3

你有很多钥匙=＆gt;值哈希包含一个键（在箭头之前）和一个值（在箭头之后）

你可以制作一个哈希数组。 Ruby on rails使用它。

您必须修改引号

customer_hash = {
    "Ken" => "Fiction",
    "William" => "Mystery",
    "Catherine" => "Computer",
    "Mark" => "Fiction",
    "Steve" => "Sports",
    "Sam" => "Fiction"
}

但为什么不这样做

customer_array_of_hashes =  [
{'Ken' => 'Fiction'},
{'William' => 'Mystery'},
{'Catherine' => 'Computer'},
{'Mark' => 'Fiction'},
{'Steve'=> 'Sports'},
{'Sam' => 'Fiction'}
]

然后你可以像这样循环播放

customer_array_of_hashes.each do|hash|
 hash.each do |key, value|
  puts "lastname: " + value + ", firstname: " + key
 end
end

你可以在这里找到所有红宝石类的所有方法

Ruby API

并在此处使用额外的方法

Ruby on rails API

最后一个提示

试试这个

irb(main):039:0> customer_array_of_hashes.class
=> Array

如果你想在ruby中使用哪个类，那么class方法就会给出答案。

好的，你知道customer_array_of_hashes是一个数组。您可以在数组上使用的一种方法是.first

试试这个

irb(main):040:0> customer_array_of_hashes.first.class
=> Hash

好吧，这是一系列哈希！

好看！

我的琴弦有什么问题？

3 个答案: