45 lines
		
	
	
		
			1.0 KiB
		
	
	
	
		
			Markdown
		
	
	
	
	
	
			
		
		
	
	
			45 lines
		
	
	
		
			1.0 KiB
		
	
	
	
		
			Markdown
		
	
	
	
	
	
| ---
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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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| 
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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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| 
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| ```ruby
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| my_hash = {:key1 => "value", :key2 => "value2"} 
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| ```
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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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| 
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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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| 
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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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| 
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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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| 
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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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| 
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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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| 
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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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| 
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| ```ruby
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| my_hash.length # 2 
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| ```
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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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| 
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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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| ``` |