ios - 我们在 ARC 中创建对象的这两种方式之间有什么区别吗?
<p><p>我想知道两者之间实际上有什么区别:</p>
<pre><code>UIButton *deleteButton = ;
self.deleteButton = deleteButton;
</code></pre>
<p>和:</p>
<pre><code>self.deleteButton = ;
</code></pre>
<p>当使用 ARC 时?</p>
<p>我看到很多人在第一种情况下写了很多代码,但我相信第二种方式更短,更清晰简洁。</p></p>
<br><hr><h1><strong>Best Answer-推荐答案</ strong></h1><br>
<p><blockquote>
<p>is there actually any difference between</p>
</blockquote>
<p>是的,但是在编译器优化下,生成的二进制文件将是相同的。</p>
<p><code>UIButton *deleteButton</code>,即<code>UIButton __strong *deleteButton</code>拥有该对象的所有权。</p>
<p>对象已在当前自动释放池中注册,因为 <code>buttonWithType:</code> 类方法不以“alloc”、“new”、“copy”或“mutableCopy”开头。</p>
<p>因此,</p>
<pre><code>UIButton *deleteButton = ;
/*
* The current Autorelease Pool has ownership of the object. retainCount=1
* __strong deleteButton has ownership of the object as well. retainCount=2
*/
self.deleteButton = deleteButton;
/*
* If self.deleteButton is strong property, it has ownership of the object too. retainCount=3
* If self.deleteButton is weak property, it doesn't have ownership of the object. retainCount=2
*/
</code></pre></p>
<p style="font-size: 20px;">关于ios - 我们在 ARC 中创建对象的这两种方式之间有什么区别吗?,我们在Stack Overflow上找到一个类似的问题:
<a href="https://stackoverflow.com/questions/31251139/" rel="noreferrer noopener nofollow" style="color: red;">
https://stackoverflow.com/questions/31251139/
</a>
</p>
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