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var_dump

打印變量的相關信息
名稱:var_dump
分類:變量處理
所屬語言:php
一句話介紹:轉儲有關一個或多個變量的信息。

實例

轉儲有關不同變量的信息:

 <span class="token php language-php"><span class="token delimiter important"><?php</span>
<span class="token variable">$a</span> <span class="token operator">=</span> <span class="token number">32</span> <span class="token punctuation">;</span>
<span class="token keyword">echo</span> <span class="token function">var_dump</span> <span class="token punctuation">(</span> <span class="token variable">$a</span> <span class="token punctuation">)</span> <span class="token operator">.</span> <span class="token string double-quoted-string">"<br>"</span> <span class="token punctuation">;</span>

<span class="token variable">$b</span> <span class="token operator">=</span> <span class="token string double-quoted-string">"Hello world!"</span> <span class="token punctuation">;</span>
<span class="token keyword">echo</span> <span class="token function">var_dump</span> <span class="token punctuation">(</span> <span class="token variable">$b</span> <span class="token punctuation">)</span> <span class="token operator">.</span> <span class="token string double-quoted-string">"<br>"</span> <span class="token punctuation">;</span>

<span class="token variable">$c</span> <span class="token operator">=</span> <span class="token number">32.5</span> <span class="token punctuation">;</span>
<span class="token keyword">echo</span> <span class="token function">var_dump</span> <span class="token punctuation">(</span> <span class="token variable">$c</span> <span class="token punctuation">)</span> <span class="token operator">.</span> <span class="token string double-quoted-string">"<br>"</span> <span class="token punctuation">;</span>

<span class="token variable">$d</span> <span class="token operator">=</span> <span class="token keyword">array</span> <span class="token punctuation">(</span> <span class="token string double-quoted-string">"red"</span> <span class="token punctuation">,</span> <span class="token string double-quoted-string">"green"</span> <span class="token punctuation">,</span> <span class="token string double-quoted-string">"blue"</span> <span class="token punctuation">)</span> <span class="token punctuation">;</span>
<span class="token keyword">echo</span> <span class="token function">var_dump</span> <span class="token punctuation">(</span> <span class="token variable">$d</span> <span class="token punctuation">)</span> <span class="token operator">.</span> <span class="token string double-quoted-string">"<br>"</span> <span class="token punctuation">;</span>

<span class="token variable">$e</span> <span class="token operator">=</span> <span class="token keyword">array</span> <span class="token punctuation">(</span> <span class="token number">32</span> <span class="token punctuation">,</span> <span class="token string double-quoted-string">"Hello world!"</span> <span class="token punctuation">,</span> <span class="token number">32.5</span> <span class="token punctuation">,</span> <span class="token keyword">array</span> <span class="token punctuation">(</span> <span class="token string double-quoted-string">"red"</span> <span class="token punctuation">,</span> <span class="token string double-quoted-string">"green"</span> <span class="token punctuation">,</span> <span class="token string double-quoted-string">"blue"</span> <span class="token punctuation">)</span> <span class="token punctuation">)</span> <span class="token punctuation">;</span>
<span class="token keyword">echo</span> <span class="token function">var_dump</span> <span class="token punctuation">(</span> <span class="token variable">$e</span> <span class="token punctuation">)</span> <span class="token operator">.</span> <span class="token string double-quoted-string">"<br>"</span> <span class="token punctuation">;</span>

<span class="token comment">// Dump two variables</span>
<span class="token keyword">echo</span> <span class="token function">var_dump</span> <span class="token punctuation">(</span> <span class="token variable">$a</span> <span class="token punctuation">,</span> <span class="token variable">$b</span> <span class="token punctuation">)</span> <span class="token operator">.</span> <span class="token string double-quoted-string">"<br>"</span> <span class="token punctuation">;</span>
<span class="token delimiter important">?></span></span>

親自試一試

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