Betul dan Salah dalam PHP

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Apabila menggunakan false, ia tidak menunjukkan sebarang output. Perlu diingat bahawa pelayar sentiasa memaparkan nilai ini sebagai rentetan. false 时，它不显示任何输出。值得注意的是，浏览器总是以字符串的形式呈现这些值。

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在 php 中使用 true 和 false 作为布尔逻辑值

布尔值是逻辑值。它们可以是真或假。

两者在 php 中都是区分大小写的，也是 php 中的简单数据类型。

<code><code class="language-php hljs" data-lang="php"><span style="display:flex;"><span> <span style="color:#19177c">$true</span> <span style="color:#666">=</span> <span style="color:#008000;font-weight:bold">True</span>; <span style="color:#408080;font-style:italic">//returns 1 
</span></span></span><span style="display:flex;"><span><span style="color:#408080;font-style:italic"></span> <span style="color:#19177c">$false</span> <span style="color:#666">=</span> <span style="color:#008000;font-weight:bold">False</span>; <span style="color:#408080;font-style:italic">// return nothing 
</span></span></span><span style="display:flex;"><span><span style="color:#408080;font-style:italic"></span><span style="color:#008000;font-weight:bold">echo</span> <span style="color:#19177c">$true</span><span style="color:#666">.</span>PHP_EOL;
</span></span><span style="display:flex;"><span><span style="color:#008000;font-weight:bold">echo</span> <span style="color:#19177c">$false</span>;
</span></span><span style="display:flex;"><span><span style="color:#408080;font-style:italic">//using comparis<strong class="keylink">io</strong>n operator to check boolean values
</span></span></span><span style="display:flex;"><span><span style="color:#408080;font-style:italic"></span><span style="color:#008000;font-weight:bold">if</span> (<span style="color:#19177c">$a</span> <span style="color:#666">==</span> <span style="color:#ba2121">"abc"</span>) {
</span></span><span style="display:flex;"><span><span style="color:#008000;font-weight:bold">echo</span> <span style="color:#ba2121">"return boolean value"</span>; <span style="color:#408080;font-style:italic">//returns nothing since $a is not equal to abc thus it is a false
</span></span></span><span style="display:flex;"><span><span style="color:#408080;font-style:italic"></span> }
</span></span><span style="display:flex;"><span><span style="color:#008000;font-weight:bold">if</span> (<span style="color:#008000;font-weight:bold">TRUE</span>) {
</span></span><span style="display:flex;"><span>	<span style="color:#408080;font-style:italic">//because true means true
</span></span></span><span style="display:flex;"><span><span style="color:#408080;font-style:italic"></span><span style="color:#008000;font-weight:bold">echo</span> <span style="color:#ba2121">"Your condition is executed!"</span><span style="color:#666">.</span>PHP_EOL; 
</span></span><span style="display:flex;"><span>}
</span></span><span style="display:flex;"><span><span style="color:#008000;font-weight:bold">if</span> (<span style="color:#008000;font-weight:bold">false</span>) {
</span></span><span style="display:flex;"><span><span style="color:#008000;font-weight:bold">echo</span> <span style="color:#ba2121">"It will print nothing"</span>; <span style="color:#408080;font-style:italic">//false returns nothing
</span></span></span><span style="display:flex;"><span><span style="color:#408080;font-style:italic"></span> }
</span></span><span style="display:flex;"><span><span style="color:#408080;font-style:italic">//Determine integer comparisions with boolean values
</span></span></span><span style="display:flex;"><span><span style="color:#408080;font-style:italic"></span><span style="color:#008000;font-weight:bold">echo</span> <span style="color:#666">5</span><span style="color:#666"><</span><span style="color:#666">10</span>; <span style="color:#408080;font-style:italic">//returns 1 since 5 is actually less ten (condition true)
</span></span></span><span style="display:flex;"><span><span style="color:#408080;font-style:italic"></span><span style="color:#008000;font-weight:bold">echo</span> <span style="color:#666">10</span> <span style="color:#666">!=</span> <span style="color:#666">5</span>; <span style="color:#408080;font-style:italic">//returns 1 (true)
</span></span></span><span style="display:flex;"><span><span style="color:#408080;font-style:italic"></span><span style="color:#008000;font-weight:bold">echo</span> <span style="color:#666">5</span> <span style="color:#666">==</span> <span style="color:#666">4</span>; <span style="color:#408080;font-style:italic">//false
</span></span></span></code></code>

输出：

<code><code class="language-text hljs" data-lang="text"><span style="display:flex;"><span>1 
</span></span><span style="display:flex;"><span>Your condition is executed!
</span></span><span style="display:flex;"><span>11
</span></span></code></code>

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在 PHP 中使用 var_dump() 函数确定布尔值

我们还可以在 php.ini 中转换布尔值。让我们首先了解这些参数的一些预定义值分配。

如果我们将以下值转换为布尔值，它们将被视为假

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Gunakan true< dalam <strong class="keylink">php</strong> / code> dan <code>false sebagai nilai logik Boolean

Nilai Boolean adalah nilai logik. Ia boleh menjadi true atau false.

• Kedua-duanya sensitif huruf besar dalam php dan merupakan jenis data ringkas dalam php. false 是 false

  <code><code class="language-php hljs" data-lang="php"><span style="display:flex;"><span><span style="color:#666"><?</span>php
  </span></span><span style="display:flex;"><span>var_dump((bool) <span style="color:#008000;font-weight:bold">false</span>);<span style="color:#408080;font-style:italic">//(false)
  </span></span></span><span style="display:flex;"><span><span style="color:#408080;font-style:italic"></span>var_dump((bool) <span style="color:#ba2121">"0"</span>); <span style="color:#408080;font-style:italic">//(false)
  </span></span></span><span style="display:flex;"><span><span style="color:#408080;font-style:italic"></span>var_dump((bool) <span style="color:#666">0.0</span>);<span style="color:#408080;font-style:italic">//(false)
  </span></span></span><span style="display:flex;"><span><span style="color:#408080;font-style:italic"></span>var_dump((bool) <span style="color:#666">-</span><span style="color:#666">0.0</span>);<span style="color:#408080;font-style:italic">//(false)
  </span></span></span><span style="display:flex;"><span><span style="color:#408080;font-style:italic"></span>var_dump((bool) <span style="color:#008000;font-weight:bold">NULL</span>); <span style="color:#408080;font-style:italic">//(false)
  </span></span></span><span style="display:flex;"><span><span style="color:#408080;font-style:italic"></span>var_dump((bool) <span style="color:#008000;font-weight:bold">array</span>()); <span style="color:#408080;font-style:italic">//(false)
  </span></span></span><span style="display:flex;"><span><span style="color:#408080;font-style:italic">//true bools (a few examples)
  </span></span></span><span style="display:flex;"><span><span style="color:#408080;font-style:italic"></span>var_dump((bool)<span style="color:#008000;font-weight:bold">true</span>);<span style="color:#408080;font-style:italic">//true
  </span></span></span><span style="display:flex;"><span><span style="color:#408080;font-style:italic"></span>var_dump((bool)<span style="color:#666">1</span>);<span style="color:#408080;font-style:italic">//true
  </span></span></span><span style="display:flex;"><span><span style="color:#408080;font-style:italic"></span>var_dump((bool)<span style="color:#666">100</span>); <span style="color:#408080;font-style:italic">//true
  </span></span></span><span style="display:flex;"><span><span style="color:#408080;font-style:italic"></span>var_dump((bool) <span style="color:#008000;font-weight:bold">array</span>(<span style="color:#666">65</span>)); <span style="color:#408080;font-style:italic">//true
  </span></span></span><span style="display:flex;"><span><span style="color:#408080;font-style:italic"></span><span style="color:#bc7a00">?></span><span >
  </span></span></span></code></code>

  Output:

• <code><code class="language-text hljs" data-lang="text"><span style="display:flex;"><span>bool(false)
  </span></span><span style="display:flex;"><span>bool(false)
  </span></span><span style="display:flex;"><span>bool(true)
  </span></span><span style="display:flex;"><span>bool(false)
  </span></span><span style="display:flex;"><span>bool(false)
  </span></span><span style="display:flex;"><span>bool(false)
  </span></span><span style="display:flex;"><span>bool(false)
  </span></span><span style="display:flex;"><span>bool(true)
  </span></span><span style="display:flex;"><span>bool(true)
  </span></span><span style="display:flex;"><span>bool(true)
  </span></span><span style="display:flex;"><span>bool(true)
  </span></span></code></code>

  ---

  Gunakan fungsi var_dump() dalam PHP untuk menentukan nilai boolean0 也是 falseKami juga boleh menukar nilai boolean dalam php.ini. Mari kita fahami beberapa penetapan nilai pratakrif dahulu untuk parameter ini.

• Jika kita menukar nilai berikut kepada boolean, nilai tersebut akan dianggap sebagai false: 0.0 和 -0.0 之类的浮点数也是 false
• 0 元素的数组是 false.
• NULL 是 false.
Seperti

. true。

我们可以借助转储布尔值信息的 var_dump() 函数来确定布尔值。

让我们用 var_dump

mempunyai

.

🎜🎜. 🎜 🎜🎜Sebaliknya, semua nilai lain dianggap benar. 🎜🎜Kita boleh menentukan nilai Boolean dengan bantuan fungsi var_dump() yang membuang maklumat nilai Boolean. 🎜🎜Mari kami gunakan var_dump untuk menyemak jenis ralat yang disebutkan di atas: 🎜rrreee 🎜Output: 🎜rrreee

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