blocks|key|975550|text|我认为.send方法最有用的特性之一是它可以动态地调用方法。这可以节省你大量的打字时间。.send方法最流行的用法之一是动态分配属性。例如：|type|unstyled|depth|inlineStyleRanges|entityRanges|data|975551|class+Car
++attr_accessor+:make,+:model,+:year
end++|code-block|syntax|javascript|975552|要定期分配属性，需要执行以下操作|975553|c+=+Car.new
c.make="Honda"
c.model="CRV"
c.year="2014"|975554|或者使用.send方法：|975555|c.send("make=",+"Honda")
c.send("model=",+"CRV")
c.send("year=","2014")|975556|但它可以全部替换为以下内容：|975557|假设您的Rails应用程序需要从用户输入中将属性分配给您的汽车类，您可以这样做|975558|c+=+Car.new()
params.each+do+%7Ckey,+value%7C
++c.send("#{key}=",+value)
end|975559|entityMap^0|0|0|0|0|0|0|0|0|0^^$0|@$1|2|3|4|5|6|7|W|8|@]|9|@]|A|$]]|$1|B|3|C|5|D|7|X|8|@]|9|@]|A|$E|F]]|$1|G|3|H|5|6|7|Y|8|@]|9|@]|A|$]]|$1|I|3|J|5|D|7|Z|8|@]|9|@]|A|$E|F]]|$1|K|3|L|5|6|7|10|8|@]|9|@]|A|$]]|$1|M|3|N|5|D|7|11|8|@]|9|@]|A|$E|F]]|$1|O|3|P|5|6|7|12|8|@]|9|@]|A|$]]|$1|Q|3|R|5|6|7|13|8|@]|9|@]|A|$]]|$1|S|3|T|5|D|7|14|8|@]|9|@]|A|$E|F]]|$1|U|3|-4|5|6|7|15|8|@]|9|@]|A|$]]]|V|$]]

One of the most useful feature I think with .send method is that it can dynamically call on method. This can save you a lot of typing. One of the most popular use of .send method is to assign attributes dynamically. For example:

<pre><code>class Car
 attr_accessor :make, :model, :year
end 
</code></pre>

To assign attributes regularly one would need to 

<pre><code>c = Car.new
c.make="Honda"
c.model="CRV"
c.year="2014"
</code></pre>

Or using .send method:

<pre><code>c.send("make=", "Honda")
c.send("model=", "CRV")
c.send("year=","2014")
</code></pre>

But it can all be replaced with the following:

Assuming your Rails app needs to assign attributes to your car class from user input, you can do

<pre><code>c = Car.new()
params.each do |key, value|
 c.send("#{key}=", value)
end
</code></pre>

blocks|key|975644|text|另一个示例，类似于Antonio+Jha的https://stackoverflow.com/a/26193804/1897857|type|unstyled|depth|inlineStyleRanges|entityRanges|offset|length|data|975645|是否需要读取对象的属性。|975646|例如，如果你有一个字符串数组，如果你试图遍历它们并在你的对象上调用它们，它就不会起作用。|975647|atts+=+['name',+'description']
@project+=+Project.first
atts.each+do+%7Ca%7C
++puts+@project.a
end
#+=>+NoMethodError:+undefined+method+`a'|code-block|syntax|javascript|975648|但是，您可以将字符串send到对象：|style|CODE|975649|atts+=+['name',+'description']
@project+=+Project.first
atts.each+do+%7Ca%7C
++puts+@project.send(a)
end
#+=>+Vandalay+Project
#+=>+A+very+important+project|975650|entityMap|0|LINK|mutability|MUTABLE|url|https://stackoverflow.com/a/26193804/1897857^0|L|18|0|0|0|0|0|A|4|0|0^^$0|@$1|2|3|4|5|6|7|10|8|@]|9|@$A|11|B|12|1|13]]|C|$]]|$1|D|3|E|5|6|7|14|8|@]|9|@]|C|$]]|$1|F|3|G|5|6|7|15|8|@]|9|@]|C|$]]|$1|H|3|I|5|J|7|16|8|@]|9|@]|C|$K|L]]|$1|M|3|N|5|6|7|17|8|@$A|18|B|19|O|P]]|9|@]|C|$]]|$1|Q|3|R|5|J|7|1A|8|@]|9|@]|C|$K|L]]|$1|S|3|-4|5|6|7|1B|8|@]|9|@]|C|$]]]|T|$U|$5|V|W|X|C|$Y|Z]]]]

Another example, similar to Antonio Jha's <a href="https://stackoverflow.com/a/26193804/1897857">https://stackoverflow.com/a/26193804/1897857</a>

is if you need to read attributes on an object.

For example, if you have an array of strings, if you try to iterate through them and call them on your object, it won't work.

<pre><code>atts = ['name', 'description']
@project = Project.first
atts.each do |a|
 puts @project.a
end
# =&gt; NoMethodError: undefined method `a'
</code></pre>

However, you can <code>send</code> the strings to the object:

<pre><code>atts = ['name', 'description']
@project = Project.first
atts.each do |a|
 puts @project.send(a)
end
# =&gt; Vandalay Project
# =&gt; A very important project
</code></pre>

blocks|key|975711|text|视图的另一个用例：|type|unstyled|depth|inlineStyleRanges|entityRanges|data|975712|++++<%25=+link_to+
++++send("first_part_of_path_#{some_dynamic_parameters}_end_path",+
++++attr1,+attr2),+....
++++%25>|code-block|syntax|javascript|975713|允许。您需要编写可伸缩的视图，这些视图可以处理所有类型的对象：|975714|++++render+'your_view_path',+object:+"my_object"|975715|entityMap^0|0|0|0|0^^$0|@$1|2|3|4|5|6|7|M|8|@]|9|@]|A|$]]|$1|B|3|C|5|D|7|N|8|@]|9|@]|A|$E|F]]|$1|G|3|H|5|6|7|O|8|@]|9|@]|A|$]]|$1|I|3|J|5|D|7|P|8|@]|9|@]|A|$E|F]]|$1|K|3|-4|5|6|7|Q|8|@]|9|@]|A|$]]]|L|$]]

Another use case for views:

<pre><code> &lt;%= link_to 
 send("first_part_of_path_#{some_dynamic_parameters}_end_path", 
 attr1, attr2), ....
 %&gt;
</code></pre>

Allow . you to write scalable view who work with all kind of objects
with: 

<pre><code> render 'your_view_path', object: "my_object"
</code></pre>

blocks|key|975767|text|发送是做什么的？|type|unstyled|depth|inlineStyleRanges|entityRanges|data|975768|send是“调用方法”的另一种方式。示例：|offset|length|style|CODE|975769|o+=+Object.new
o.send(:to_s)+#+=>+"#<Object:0x00005614d7a24fa3>"
#+is+equivalent+to:
o.to_s+#+=>+"#<Object:0x00005614d7a24fa3>"|code-block|syntax|javascript|975770|Send+lives+in+the+Object+class。|975771|这有什么好处？|975772|这种方法的好处是，您可以传入要作为参数调用的方法。下面是一个简单的例子：|975773|def+dynamically_call_a_method(method_name)
++++o+=+Object.new
++++o.send+method_name
end
dynamically_call_a_method(:to_s)+#+=>+"#<Object:0x00005614d7a24fa3>"|975774|您可以传入希望被调用的方法。在本例中，我们传入了:to_s。这在做ruby元编程时非常方便，因为这允许我们根据不同的需求调用不同的方法。|975775|entityMap|0|LINK|mutability|MUTABLE|url|https://ruby-doc.org/core-2.6.5/Object.html#method-i-send^0|0|0|4|0|0|0|U|0|0|0|0|0|O|5|0^^$0|@$1|2|3|4|5|6|7|14|8|@]|9|@]|A|$]]|$1|B|3|C|5|6|7|15|8|@$D|16|E|17|F|G]]|9|@]|A|$]]|$1|H|3|I|5|J|7|18|8|@]|9|@]|A|$K|L]]|$1|M|3|N|5|6|7|19|8|@]|9|@$D|1A|E|1B|1|1C]]|A|$]]|$1|O|3|P|5|6|7|1D|8|@]|9|@]|A|$]]|$1|Q|3|R|5|6|7|1E|8|@]|9|@]|A|$]]|$1|S|3|T|5|J|7|1F|8|@]|9|@]|A|$K|L]]|$1|U|3|V|5|6|7|1G|8|@$D|1H|E|1I|F|G]]|9|@]|A|$]]|$1|W|3|-4|5|6|7|1J|8|@]|9|@]|A|$]]]|X|$Y|$5|Z|10|11|A|$12|13]]]]

<h3>What does send do?</h3>
<code>send</code> is another way of &quot;calling a method&quot;. Example:
<pre><code>o = Object.new
o.send(:to_s) # =&gt; &quot;#&lt;Object:0x00005614d7a24fa3&gt;&quot;
# is equivalent to:
o.to_s # =&gt; &quot;#&lt;Object:0x00005614d7a24fa3&gt;&quot;
</code></pre>
<a href="https://ruby-doc.org/core-2.6.5/Object.html#method-i-send" rel="nofollow noreferrer">Send lives in the Object class</a>.
<h3>What is the benefit of ths?</h3>
The benefit of this approach is that you can pass in the method you want to call as a parameter. Here is a simple example:
<pre><code>def dynamically_call_a_method(method_name)
 o = Object.new
 o.send method_name
end
dynamically_call_a_method(:to_s) # =&gt; &quot;#&lt;Object:0x00005614d7a24fa3&gt;&quot;
</code></pre>
You can pass in the method you want to be called. In this case we passed in <code>:to_s</code>. This can be very handy when doing ruby metaprogramming, because this allows us to call different methods according to our different requirements.

blocks|key|1190092|text|Send还可以用来显示Ruby中的所有东西都是对象|type|unstyled|depth|inlineStyleRanges|entityRanges|data|1190093|1.send(:%2B,+1)++##+->+2
3.send(:*,+2)++##+->+6|code-block|syntax|javascript|1190094|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|$]]

Send can also be used as a way of showing how everything in Ruby is an object
<pre><code>1.send(:+, 1) ## -&gt; 2
3.send(:*, 2) ## -&gt; 6
</code></pre>

Can someone please tell me what

<pre><code>send("#{Model.find...}")
</code></pre>

is and does?

What does send() do in Ruby?

有没有人能告诉我send("#{Model.find...}")现在和现在是吗？

问send()在Ruby中做什么？
EN

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