is_numeric

Beispiel

Überprüfen Sie, ob die Variable eine numerische oder eine numerische Zeichenfolge ist:

 <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 string double-quoted-string">"a ist"</span> <span class="token operator">.</span> <span class="token function">is_numeric</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 number">0</span> <span class="token punctuation">;</span>
<span class="token keyword">Echo</span> <span class="token string double-quoted-string">"B ist"</span> <span class="token operator">.</span> <span class="token function">is_numeric</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 string double-quoted-string">"C ist"</span> <span class="token operator">.</span> <span class="token function">is_numeric</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 string double-quoted-string">"32"</span> <span class="token punctuation">;</span>
<span class="token keyword">Echo</span> <span class="token string double-quoted-string">"D ist"</span> <span class="token operator">.</span> <span class="token function">is_numeric</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 constant boolean">true</span> <span class="token punctuation">;</span>
<span class="token keyword">echo</span> <span class="token string double-quoted-string">"e ist"</span> <span class="token operator">.</span> <span class="token function">is_numeric</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 variable">$ f</span> <span class="token operator">=</span> <span class="token constant">null</span> <span class="token punctuation">;</span>
<span class="token keyword">echo</span> <span class="token string double-quoted-string">"f ist"</span> <span class="token operator">.</span> <span class="token function">is_numeric</span> <span class="token punctuation">(</span> <span class="token variable">$ f</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>

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