45 lines
1.0 KiB
Markdown
45 lines
1.0 KiB
Markdown
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---
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title: Ruby Hash
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localeTitle: Ruby哈希
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---
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## Ruby哈希
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哈希表示不同键，值对的集合。它也被称为关联数组。要在Ruby中创建哈希，请使用大括号并使用逗号分隔每个键值对。
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```ruby
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my_hash = {:key1 => "value", :key2 => "value2"}
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```
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您可以通过以下方式创建哈希
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```ruby
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my_hash = Hash.new # with empty hash
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my_hash = {:key1 => "value", :key2 => "value2"} # with key's and value's defined
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```
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您可以使用方括号和键引用访问哈希中键的值
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```ruby
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my_hash[:key1] # value
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my_hash[:key2] # value2
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```
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您可以为已定义的哈希分配新密钥和值
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```ruby
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my_hash[:key3] = "value3" # {:key1=>"value", :key2=>"value2", :key3=>"value3"}
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```
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您可以使用`length`方法检查哈希的元素数量：
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```ruby
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my_hash.length # 2
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```
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您也可以将整数创建为散列键，但语法与通常的不同
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```ruby
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my_hash = {1: "value"} # will raise an exception
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my_hash = {1 => "value"} # will create hash with corresponding key value pair
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```
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