count_chars
文字列で使用される文字に関する情報を返します - 各バイト値(0..255)が文字列で発生する回数をカウントします
「Hello World!」で使用されているすべての異なる文字を含む文字列を返します。 (モード3):
<span class="token php language-php"><span class="token delimiter important"><?php</span> <span class="token variable">$ str</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">count_chars</span> <span class="token punctuation">(</span> <span class="token variable">$ str</span> <span class="token punctuation">、</span> <span class="token number">3</span> <span class="token punctuation">)</span> <span class="token punctuation">;</span> <span class="token delimiter important">?></span></span>
「Hello World!」で使用されていないすべての文字を含む文字列を返します。 (スキーマ4):
<span class="token php language-php"><span class="token delimiter important"><?php</span> <span class="token variable">$ str</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">count_chars</span> <span class="token punctuation">(</span> <span class="token variable">$ str</span> <span class="token punctuation">、</span> <span class="token number">4</span> <span class="token punctuation">)</span> <span class="token punctuation">;</span> <span class="token delimiter important">?></span></span>
この例では、count_chars()を使用して文字列をチェックします。リターンモードが1に設定されています。モード1は、キー名としてASCII値を持つ配列を返し、発生数はキー値です。
<span class="token php language-php"><span class="token delimiter important"><?php</span> <span class="token variable">$ str</span> <span class="token operator">=</span> <span class="token string double-quoted-string">"hello world!"</span> <span class="token punctuation">;</span> <span class="token function">print_r</span> <span class="token punctuation">(</span> <span class="token function">count_chars</span> <span class="token punctuation">(</span> <span class="token variable">$ str</span> <span class="token punctuation">、</span> <span class="token number">1</span> <span class="token punctuation">)</span> <span class="token punctuation">)</span> <span class="token punctuation">;</span> <span class="token delimiter important">?></span></span>
ASCII文字が文字列に表示される回数をカウントする別の例:
<span class="token php language-php"><span class="token delimiter important"><?php</span> <span class="token variable">$ str</span> <span class="token operator">=</span> <span class="token string double-quoted-string">"phpはかなり楽しいです!!"</span> <span class="token punctuation">;</span> <span class="token variable">$ strarray</span> <span class="token operator">=</span> <span class="token function">count_chars</span> <span class="token punctuation">(</span> <span class="token variable">$ str</span> <span class="token punctuation">、</span> <span class="token number">1</span> <span class="token punctuation">)</span> <span class="token punctuation">;</span> <span class="token keyword">foreach</span> <span class="token punctuation">(</span> <span class="token variable">$ strarray</span> <span class="token keyword">as</span> <span class="token variable">$ key</span> <span class="token operator">=></span> <span class="token variable">$ value</span> <span class="token punctuation">)</span> <span class="token punctuation">{</span> <span class="token keyword">エコー</span><span class="token string double-quoted-string">「キャラクター<b> '」</span> <span class="token operator">。</span> <span class="token function">chr</span> <span class="token punctuation">(</span> <span class="token variable">$ key</span> <span class="token punctuation">)</span> <span class="token operator">。</span> <span class="token string double-quoted-string">"</b>は<span class="token interpolation"><span class="token variable">$ value</span></span> times。<br>"</span> <span class="token punctuation">;</span> <span class="token punctuation">}</span> <span class="token delimiter important">?></span></span>