is_integer

Beispiel

Überprüfen Sie, ob die Variable ein ganzzahliger Typ 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_integer</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_integer</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_integer</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_integer</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_integer</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 string double-quoted-string">"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_integer</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>

Probieren Sie es selbst aus

Beispiel Erklärung:

In PHP ist weder der boolesche Wert true noch die Zeichenfolge "32" ein ganzzahliger Typ, auch wenn die Zeichenfolge Zahlen enthält. Schecks für $d und $e werden also FALSE zurückgeben. In ähnlicher Weise ist $f eine Zeichenfolge, und obwohl sein Inhalt "null" ist, ist es auch kein ganzzahliger Typ, sodass der Scheck FALSE zurückgibt. Schwimmpunktzahlen wie $c sind offensichtlich keine Ganzzahlen, so dass is_int($c) auch FALSE zurückgibt.