blocks|key|2746561|text|def+initialize(params)
++params.each+do+%7Ckey,+value%7C
++++instance_variable_set("@#{key}",+value)
++end
end|type|code-block|depth|inlineStyleRanges|entityRanges|data|syntax|javascript|2746562|unstyled|entityMap^0|0^^$0|@$1|2|3|4|5|6|7|G|8|@]|9|@]|A|$B|C]]|$1|D|3|-4|5|E|7|H|8|@]|9|@]|A|$]]]|F|$]]

<pre><code>def initialize(params)
 params.each do |key, value|
 instance_variable_set("@#{key}", value)
 end
end
</code></pre>

blocks|key|2746570|text|您可以遍历这些键并调用setter。我更喜欢这样，因为如果你传递了一个无效的密钥，它就会被捕获。|type|unstyled|depth|inlineStyleRanges|entityRanges|data|2746571|class+Foo
++attr_accessor+:name,+:age,+:email,+:gender,+:height

++def+initialize+params+=+{}
++++params.each+{+%7Ckey,+value%7C+send+"#{key}=",+value+}
++end
end

foo+=+Foo.new+name:+'Josh',+age:+456
foo.name++#+=>+"Josh"
foo.age+++#+=>+456
foo.email+#+=>+nil|code-block|syntax|javascript|2746572|entityMap^0|0|0^^$0|@$1|2|3|4|5|6|7|I|8|@]|9|@]|A|$]]|$1|B|3|C|5|D|7|J|8|@]|9|@]|A|$E|F]]|$1|G|3|-4|5|6|7|K|8|@]|9|@]|A|$]]]|H|$]]

You can just iterate over the keys and invoke the setters. I prefer this, because it will catch if you pass an invalid key.

<pre><code>class Foo
 attr_accessor :name, :age, :email, :gender, :height

 def initialize params = {}
 params.each { |key, value| send "#{key}=", value }
 end
end

foo = Foo.new name: 'Josh', age: 456
foo.name # =&gt; "Josh"
foo.age # =&gt; 456
foo.email # =&gt; nil
</code></pre>

blocks|key|3227861|text|如果您正在接收一个散列作为唯一的参数，为什么不将其作为一个实例变量呢？当你需要一个值的时候，从散列中调用它。您可以保持实例变量名简短，以便可以轻松地调用它。|type|unstyled|depth|inlineStyleRanges|entityRanges|data|3227862|class+Foo
++attr_reader+:p
++def+initalize+p
++++@p+=+p
++end
++def+foo
++++do_something_with(@p[:name])
++++...
++end
end|code-block|syntax|javascript|3227863|如果proc对您来说仍然太长，那么您可以将@p[:name]保存为实例变量，并调用相关的值，如@p.(:name)。|offset|length|style|CODE|3227864|class+Foo
++attr_reader+:p
++def+initialize+p
++++@p+=+->x{p[x]}
++end
++def+foo
++++do_something_with(@p.(:name))
++++...
++end
end|3227865|或者，还有一种替代方法是定义一个调用散列并应用键的方法。|3227866|class+Foo
++def+initalize+p
++++@p+=+p
++end
++def+get+key
++++@p[key]
++end
++def+foo
++++do_something_with(get(:name))
++++...
++end
end|3227867|如果想要设置这些值，可以定义一个setter方法，如果需要，还可以进一步检查无效的键。|3227868|class+Foo
++Keys+=+[:name,+:age,+:email,+:gender,+:height]
++def+initalize+p
++++raise+"Invalid+key+in+argument"+unless+(p.keys+-+Keys).empty?
++++@p+=+p
++end
++def+set+key,+value
++++raise+"Invalid+key"+unless+Keys.key?(key)
++++@p[key]+=+value
++end
++def+get+key
++++@p[key]
++end
++def+foo
++++do_something_with(get(:name))
++++...
++end
end|3227869|entityMap^0|0|0|L|9|1B|A|0|0|0|0|0|0^^$0|@$1|2|3|4|5|6|7|Y|8|@]|9|@]|A|$]]|$1|B|3|C|5|D|7|Z|8|@]|9|@]|A|$E|F]]|$1|G|3|H|5|6|7|10|8|@$I|11|J|12|K|L]|$I|13|J|14|K|L]]|9|@]|A|$]]|$1|M|3|N|5|D|7|15|8|@]|9|@]|A|$E|F]]|$1|O|3|P|5|6|7|16|8|@]|9|@]|A|$]]|$1|Q|3|R|5|D|7|17|8|@]|9|@]|A|$E|F]]|$1|S|3|T|5|6|7|18|8|@]|9|@]|A|$]]|$1|U|3|V|5|D|7|19|8|@]|9|@]|A|$E|F]]|$1|W|3|-4|5|6|7|1A|8|@]|9|@]|A|$]]]|X|$]]

If you are receiving a hash as the sole argument, why not just keep that as an instance variable? Whenever you need a value, call it from the hash. You can keep the instance variable name short so that it can be easily called.

<pre><code>class Foo
 attr_reader :p
 def initalize p
 @p = p
 end
 def foo
 do_something_with(@p[:name])
 ...
 end
end
</code></pre>

If <code>@p[:name]</code> is still too lengthy for you, then you can save a proc as an instance variable, and call the relevant value like <code>@p.(:name)</code>.

<pre><code>class Foo
 attr_reader :p
 def initialize p
 @p = -&gt;x{p[x]}
 end
 def foo
 do_something_with(@p.(:name))
 ...
 end
end
</code></pre>

Or, still an alternative way is to define a method that calls the hash and applies the key.

<pre><code>class Foo
 def initalize p
 @p = p
 end
 def get key
 @p[key]
 end
 def foo
 do_something_with(get(:name))
 ...
 end
end
</code></pre>

If want to set the values, you can define a setter method, and further check for invalid keys if you want.

<pre><code>class Foo
 Keys = [:name, :age, :email, :gender, :height]
 def initalize p
 raise "Invalid key in argument" unless (p.keys - Keys).empty?
 @p = p
 end
 def set key, value
 raise "Invalid key" unless Keys.key?(key)
 @p[key] = value
 end
 def get key
 @p[key]
 end
 def foo
 do_something_with(get(:name))
 ...
 end
end
</code></pre>

blocks|key|2746619|text|使用params中的所有键是不正确的，您可以定义不需要的名称。我觉得应该是白名单上的名字|type|unstyled|depth|inlineStyleRanges|entityRanges|data|2746620|class+Foo
+++@@attributes+=+[:name,+:age,+:email,+:gender,+:height]++

+++@@attributes.each+do+%7Cattr%7C
+++++class_eval+{+attr_accessor+"#{attr}"+}
+++end++

+++def+initialize+params
+++++@@attributes.each+do+%7Cattr%7C
+++++++instance_variable_set("@#{attr}",+params[attr])+if+params[attr]
+++++end++
+++end
end

Foo.new({:name+=>+'test'}).name+#=>+'test'|code-block|syntax|javascript|2746621|entityMap^0|0|0^^$0|@$1|2|3|4|5|6|7|I|8|@]|9|@]|A|$]]|$1|B|3|C|5|D|7|J|8|@]|9|@]|A|$E|F]]|$1|G|3|-4|5|6|7|K|8|@]|9|@]|A|$]]]|H|$]]

Using all keys from params is not correct, you can define unwilling names. I think it should be kinda white list of names

<pre><code>class Foo
 @@attributes = [:name, :age, :email, :gender, :height] 

 @@attributes.each do |attr|
 class_eval { attr_accessor "#{attr}" }
 end 

 def initialize params
 @@attributes.each do |attr|
 instance_variable_set("@#{attr}", params[attr]) if params[attr]
 end 
 end
end

Foo.new({:name =&gt; 'test'}).name #=&gt; 'test'
</code></pre>

blocks|key|2746652|text|为什么不显式指定一个实际的参数列表呢？|type|unstyled|depth|inlineStyleRanges|entityRanges|data|2746653|class+Foo
++attr_accessor+:name,+:age,+:email,+:gender,+:height

++def+initialize(name,+age,+email,+gender,+height)
++++@name+=+name
++++@age+=+age
++++@email+=+email
++++@gender+=+gender
++++@height+=+height
++end
end|code-block|syntax|javascript|2746654|这个版本可能比其他版本的代码行更多，但它可以更容易地利用内置的语言功能(例如，参数的默认值或在调用initialize时使用不正确的参数时引发错误)。|offset|length|style|CODE|2746655|entityMap^0|0|0|1D|A|0^^$0|@$1|2|3|4|5|6|7|O|8|@]|9|@]|A|$]]|$1|B|3|C|5|D|7|P|8|@]|9|@]|A|$E|F]]|$1|G|3|H|5|6|7|Q|8|@$I|R|J|S|K|L]]|9|@]|A|$]]|$1|M|3|-4|5|6|7|T|8|@]|9|@]|A|$]]]|N|$]]

Why not just explicitly specify an actual list of arguments?

<pre><code>class Foo
 attr_accessor :name, :age, :email, :gender, :height

 def initialize(name, age, email, gender, height)
 @name = name
 @age = age
 @email = email
 @gender = gender
 @height = height
 end
end
</code></pre>

This version may be more lines of code than others, but it makes it easier to leverage built-in language features (e.g. default values for arguments or raising errors if <code>initialize</code> is called with incorrect arity).

blocks|key|4957237|text|Foo+=+Struct.new(:name,+:age,+:email,+:gender,+:height)|type|code-block|depth|inlineStyleRanges|entityRanges|data|syntax|javascript|4957238|对于一个功能齐全的类来说，这已经足够了。演示：|unstyled|4957239|p+Foo.class+#+Class

employee+=+Foo.new("smith",+29,+"smith@foo.com",+"m",+1.75)+#create+an+instance
p+employee.class+#+Foo
p+employee.methods.sort+#+huge+list+which+includes+name,+name=,+age,+age=+etc|4957240|entityMap^0|0|0|0^^$0|@$1|2|3|4|5|6|7|K|8|@]|9|@]|A|$B|C]]|$1|D|3|E|5|F|7|L|8|@]|9|@]|A|$]]|$1|G|3|H|5|6|7|M|8|@]|9|@]|A|$B|C]]|$1|I|3|-4|5|F|7|N|8|@]|9|@]|A|$]]]|J|$]]

<pre><code>Foo = Struct.new(:name, :age, :email, :gender, :height)
</code></pre>

This is enough for a fully functioning class. Demo:

<pre><code>p Foo.class # Class

employee = Foo.new("smith", 29, "smith@foo.com", "m", 1.75) #create an instance
p employee.class # Foo
p employee.methods.sort # huge list which includes name, name=, age, age= etc
</code></pre>

blocks|key|4869602|text|为了利用Joshua+Cheek的答案进行一些概括|type|unstyled|depth|inlineStyleRanges|entityRanges|data|4869603|module+Initializable
++def+initialize(params+=+{})
++++params.each+do+%7Ckey,+value%7C
++++++setter+=+"#{key}="
++++++send(setter,+value)+if+respond_to?(setter.to_sym,+false)
++++end
++end
end

class+Foo
++include+Initializable

++attr_accessor+:name,+:age,+:email,+:gender,+:height
end

Foo.new+name:+'Josh',+age:+456
=>+#<Foo:0x007fdeac02ecb0+@name="Josh",+@age=456>|code-block|syntax|javascript|4869604|NB如果已经使用了初始化混合，并且我们需要自定义初始化，我们只需调用：|offset|length|style|BOLD|4869605|class+Foo
++include+Initializable

++attr_accessor+:name,+:age,+:email,+:gender,+:height,+:handler

++def+initialize(*)
++++super

++++self.handler+=+"#{self.name}+#{self.age}"
++end
end

Foo.new+name:+'Josh',+age:+45
=>+#<Foo:0x007fe94c0446f0+@name="Josh",+@age=45,+@handler="Josh+45">+|4869606|entityMap^0|0|0|0|2|Y|1|0|0^^$0|@$1|2|3|4|5|6|7|Q|8|@]|9|@]|A|$]]|$1|B|3|C|5|D|7|R|8|@]|9|@]|A|$E|F]]|$1|G|3|H|5|6|7|S|8|@$I|T|J|U|K|L]|$I|V|J|W|K|L]]|9|@]|A|$]]|$1|M|3|N|5|D|7|X|8|@]|9|@]|A|$E|F]]|$1|O|3|-4|5|6|7|Y|8|@]|9|@]|A|$]]]|P|$]]

To capitalize on Joshua Cheek's answer with a bit of generalization

<pre><code>module Initializable
 def initialize(params = {})
 params.each do |key, value|
 setter = "#{key}="
 send(setter, value) if respond_to?(setter.to_sym, false)
 end
 end
end

class Foo
 include Initializable

 attr_accessor :name, :age, :email, :gender, :height
end

Foo.new name: 'Josh', age: 456
=&gt; #&lt;Foo:0x007fdeac02ecb0 @name="Josh", @age=456&gt;
</code></pre>

NB If the initialization mix-in has been used and we need custom initialization, we'd just call super:

<pre><code>class Foo
 include Initializable

 attr_accessor :name, :age, :email, :gender, :height, :handler

 def initialize(*)
 super

 self.handler = "#{self.name} #{self.age}"
 end
end

Foo.new name: 'Josh', age: 45
=&gt; #&lt;Foo:0x007fe94c0446f0 @name="Josh", @age=45, @handler="Josh 45"&gt; 
</code></pre>

<pre><code>class Foo
 attr_accessor :name, :age, :email, :gender, :height

 def initalize params
 @name = params[:name]
 @age = params[:age]
 @email = params[:email]
 .
 .
 .
 end
</code></pre>

This seems like a silly way of doing it. What is a better/more idiomatic way of initalizing objects in Ruby?

Ruby 1.9.3

How to cleanly initialize attributes in Ruby with new?

翻译质量差，导致语言生硬或混乱。

没有提供实际的解决方法或示例。

解答不清晰，无法理解或解决问题。

页面排版不美观，阅读体验差。

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class Foo  attr_accessor :name, :age, :email, :gender, :height  def initalize params    @name = params[:name]    @age = params[:age]    @email = params[:email] ...

问如何用new干净地初始化Ruby中的属性？
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问如何用new干净地初始化Ruby中的属性？EN