is_float

名稱:is_float

分類:變量處理

所屬語言:php

一句話介紹:檢查變量是否為浮點類型。

實例

檢查變量是否為float 類型：

 <span class="token php language-php"><span class="token delimiter important"><?php</span>
<span class="token variable">$a</span> <span class="token operator">=</span> <span class="token number">32</span> <span class="token punctuation">;</span>
<span class="token keyword">echo</span> <span class="token string double-quoted-string">"a is "</span> <span class="token operator">.</span> <span class="token function">is_float</span> <span class="token punctuation">(</span> <span class="token variable">$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">$b</span> <span class="token operator">=</span> <span class="token number">0</span> <span class="token punctuation">;</span>
<span class="token keyword">echo</span> <span class="token string double-quoted-string">"b is "</span> <span class="token operator">.</span> <span class="token function">is_float</span> <span class="token punctuation">(</span> <span class="token variable">$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">$c</span> <span class="token operator">=</span> <span class="token number">32.5</span> <span class="token punctuation">;</span>
<span class="token keyword">echo</span> <span class="token string double-quoted-string">"c is "</span> <span class="token operator">.</span> <span class="token function">is_float</span> <span class="token punctuation">(</span> <span class="token variable">$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">$d</span> <span class="token operator">=</span> <span class="token string double-quoted-string">"32"</span> <span class="token punctuation">;</span>
<span class="token keyword">echo</span> <span class="token string double-quoted-string">"d is "</span> <span class="token operator">.</span> <span class="token function">is_float</span> <span class="token punctuation">(</span> <span class="token variable">$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">$e</span> <span class="token operator">=</span> <span class="token constant boolean">true</span> <span class="token punctuation">;</span>
<span class="token keyword">echo</span> <span class="token string double-quoted-string">"e is "</span> <span class="token operator">.</span> <span class="token function">is_float</span> <span class="token punctuation">(</span> <span class="token variable">$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">$f</span> <span class="token operator">=</span> <span class="token string double-quoted-string">"null"</span> <span class="token punctuation">;</span>
<span class="token keyword">echo</span> <span class="token string double-quoted-string">"f is "</span> <span class="token operator">.</span> <span class="token function">is_float</span> <span class="token punctuation">(</span> <span class="token variable">$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 variable">$g</span> <span class="token operator">=</span> <span class="token number">1.e3</span> <span class="token punctuation">;</span>
<span class="token keyword">echo</span> <span class="token string double-quoted-string">"g is "</span> <span class="token operator">.</span> <span class="token function">is_float</span> <span class="token punctuation">(</span> <span class="token variable">$g</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>

親自試一試

注意，即使變量g使用了科學計數法表示，它仍然被視為float 類型，因此is_float($g)返回TRUE 。