array_intersect
Calculate the intersection of arrays
Compare the key values of two arrays and return the intersection:
<span class="token php language-php"><span class="token delimiter important"><?php</span> <span class="token variable">$a1</span> <span class="token operator">=</span> <span class="token keyword">array</span> <span class="token punctuation">(</span> <span class="token string double-quoted-string">"a"</span> <span class="token operator">=></span> <span class="token string double-quoted-string">"red"</span> <span class="token punctuation">,</span> <span class="token string double-quoted-string">"b"</span> <span class="token operator">=></span> <span class="token string double-quoted-string">"green"</span> <span class="token punctuation">,</span> <span class="token string double-quoted-string">"c"</span> <span class="token operator">=></span> <span class="token string double-quoted-string">"blue"</span> <span class="token punctuation">,</span> <span class="token string double-quoted-string">"d"</span> <span class="token operator">=></span> <span class="token string double-quoted-string">"yellow"</span> <span class="token punctuation">)</span> <span class="token punctuation">;</span> <span class="token variable">$a2</span> <span class="token operator">=</span> <span class="token keyword">array</span> <span class="token punctuation">(</span> <span class="token string double-quoted-string">"e"</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">"f"</span> <span class="token operator">=></span> <span class="token string double-quoted-string">"green"</span> <span class="token punctuation">,</span> <span class="token string double-quoted-string">"g"</span> <span class="token operator">=></span> <span class="token string double-quoted-string">"blue"</span> <span class="token punctuation">)</span> <span class="token punctuation">;</span> <span class="token variable">$result</span> <span class="token operator">=</span><span class="token function"></span></span><mark> <span class="token function">array_intersect</span> <span class="token punctuation">(</span> <span class="token variable">$a1</span> <span class="token punctuation">,</span> <span class="token variable">$a2</span> <span class="token punctuation">)</span></mark><span class="token punctuation"></span> <span class="token punctuation">;</span> <span class="token function">print_r</span> <span class="token punctuation">(</span> <span class="token variable">$result</span> <span class="token punctuation">)</span> <span class="token punctuation">;</span> <span class="token delimiter important">?></span>
Compare the key values of three arrays and return the intersection:
<span class="token php language-php"><span class="token delimiter important"><?php</span> <span class="token variable">$a1</span> <span class="token operator">=</span> <span class="token keyword">array</span> <span class="token punctuation">(</span> <span class="token string double-quoted-string">"a"</span> <span class="token operator">=></span> <span class="token string double-quoted-string">"red"</span> <span class="token punctuation">,</span> <span class="token string double-quoted-string">"b"</span> <span class="token operator">=></span> <span class="token string double-quoted-string">"green"</span> <span class="token punctuation">,</span> <span class="token string double-quoted-string">"c"</span> <span class="token operator">=></span> <span class="token string double-quoted-string">"blue"</span> <span class="token punctuation">,</span> <span class="token string double-quoted-string">"d"</span> <span class="token operator">=></span> <span class="token string double-quoted-string">"yellow"</span> <span class="token punctuation">)</span> <span class="token punctuation">;</span> <span class="token variable">$a2</span> <span class="token operator">=</span> <span class="token keyword">array</span> <span class="token punctuation">(</span> <span class="token string double-quoted-string">"e"</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">"f"</span> <span class="token operator">=></span> <span class="token string double-quoted-string">"black"</span> <span class="token punctuation">,</span> <span class="token string double-quoted-string">"g"</span> <span class="token operator">=></span> <span class="token string double-quoted-string">"purple"</span> <span class="token punctuation">)</span> <span class="token punctuation">;</span> <span class="token variable">$a3</span> <span class="token operator">=</span> <span class="token keyword">array</span> <span class="token punctuation">(</span> <span class="token string double-quoted-string">"a"</span> <span class="token operator">=></span> <span class="token string double-quoted-string">"red"</span> <span class="token punctuation">,</span> <span class="token string double-quoted-string">"b"</span> <span class="token operator">=></span> <span class="token string double-quoted-string">"black"</span> <span class="token punctuation">,</span> <span class="token string double-quoted-string">"h"</span> <span class="token operator">=></span> <span class="token string double-quoted-string">"yellow"</span> <span class="token punctuation">)</span> <span class="token punctuation">;</span> <span class="token variable">$result</span> <span class="token operator">=</span><span class="token function"></span></span><mark> <span class="token function">array_intersect</span> <span class="token punctuation">(</span> <span class="token variable">$a1</span> <span class="token punctuation">,</span> <span class="token variable">$a2</span> <span class="token punctuation">,</span> <span class="token variable">$a3</span> <span class="token punctuation">)</span></mark><span class="token punctuation"></span> <span class="token punctuation">;</span> <span class="token function">print_r</span> <span class="token punctuation">(</span> <span class="token variable">$result</span> <span class="token punctuation">)</span> <span class="token punctuation">;</span> <span class="token delimiter important">?></span>