array_unshift

名稱:array_unshift

分類:數組

所屬語言:php

一句話介紹:在數組開頭插入一個或多個元素。

實例

例子1

把元素"blue" 插入數組中：

 <span class="token php language-php"><span class="token delimiter important"><?php</span>
<span class="token variable">$a</span> <span class="token operator">=</span> <span class="token keyword">array</span> <span class="token punctuation">(</span> <span class="token string double-quoted-string">"a"</span> <span class="token operator">=></span> <span class="token string double-quoted-string">"red"</span> <span class="token punctuation">,</span> <span class="token string double-quoted-string">"b"</span> <span class="token operator">=></span> <span class="token string double-quoted-string">"green"</span> <span class="token punctuation">)</span> <span class="token punctuation">;</span>
<span class="token function"></span></span><mark><span class="token function">array_unshift</span> <span class="token punctuation">(</span> <span class="token variable">$a</span> <span class="token punctuation">,</span> <span class="token string double-quoted-string">"blue"</span> <span class="token punctuation">)</span></mark><span class="token punctuation"></span> <span class="token punctuation">;</span>
<span class="token function">print_r</span> <span class="token punctuation">(</span> <span class="token variable">$a</span> <span class="token punctuation">)</span> <span class="token punctuation">;</span>
<span class="token delimiter important">?></span>

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例子2

顯示返回值：

 <span class="token php language-php"><span class="token delimiter important"><?php</span>
<span class="token variable">$a</span> <span class="token operator">=</span> <span class="token keyword">array</span> <span class="token punctuation">(</span> <span class="token string double-quoted-string">"a"</span> <span class="token operator">=></span> <span class="token string double-quoted-string">"red"</span> <span class="token punctuation">,</span> <span class="token string double-quoted-string">"b"</span> <span class="token operator">=></span> <span class="token string double-quoted-string">"green"</span> <span class="token punctuation">)</span> <span class="token punctuation">;</span>
<span class="token function">print_r</span> <span class="token punctuation">(</span><span class="token function"></span></span><mark> <span class="token function">array_unshift</span> <span class="token punctuation">(</span> <span class="token variable">$a</span> <span class="token punctuation">,</span> <span class="token string double-quoted-string">"blue"</span> <span class="token punctuation">)</span></mark><span class="token punctuation"></span> <span class="token punctuation">)</span> <span class="token punctuation">;</span>
<span class="token delimiter important">?></span>

親自試一試

例子3

使用數字鍵名：

 <span class="token php language-php"><span class="token delimiter important"><?php</span>
<span class="token variable">$a</span> <span class="token operator">=</span> <span class="token keyword">array</span> <span class="token punctuation">(</span> <span class="token number">0</span> <span class="token operator">=></span> <span class="token string double-quoted-string">"red"</span> <span class="token punctuation">,</span> <span class="token number">1</span> <span class="token operator">=></span> <span class="token string double-quoted-string">"green"</span> <span class="token punctuation">)</span> <span class="token punctuation">;</span>
<span class="token function"></span></span><mark><span class="token function">array_unshift</span> <span class="token punctuation">(</span> <span class="token variable">$a</span> <span class="token punctuation">,</span> <span class="token string double-quoted-string">"blue"</span> <span class="token punctuation">)</span></mark><span class="token punctuation"></span> <span class="token punctuation">;</span>
<span class="token function">print_r</span> <span class="token punctuation">(</span> <span class="token variable">$a</span> <span class="token punctuation">)</span> <span class="token punctuation">;</span>
<span class="token delimiter important">?></span>

親自試一試