strcasecmp
二进制安全不区分大小写的字符串比较
比较两个字符串(不区分大小写):
<span class="token php language-php"><span class="token delimiter important"><?php</span> <span class="token keyword">echo</span> <span class="token function">strcasecmp</span><span class="token punctuation">(</span><span class="token string double-quoted-string">"shanghai"</span><span class="token punctuation">,</span><span class="token string double-quoted-string">"SHANGHAI"</span><span class="token punctuation">)</span><span class="token punctuation">;</span> <span class="token delimiter important">?></span></span>
比较两个字符串(不区分大小写,HELLO 和 hELLo 输出相同):
<span class="token php language-php"><span class="token delimiter important"><?php</span> <span class="token keyword">echo</span> <span class="token function">strcasecmp</span><span class="token punctuation">(</span><span class="token string double-quoted-string">"Shanghai"</span><span class="token punctuation">,</span><span class="token string double-quoted-string">"SHANGHAI"</span><span class="token punctuation">)</span><span class="token punctuation">;</span> <span class="token keyword">echo</span> <span class="token string double-quoted-string">"<br>"</span><span class="token punctuation">;</span> <span class="token keyword">echo</span> <span class="token function">strcasecmp</span><span class="token punctuation">(</span><span class="token string double-quoted-string">"Shanghai"</span><span class="token punctuation">,</span><span class="token string double-quoted-string">"sHANGHai"</span><span class="token punctuation">)</span><span class="token punctuation">;</span> <span class="token delimiter important">?></span></span>
不同的返回值:
<span class="token php language-php"><span class="token delimiter important"><?php</span> <span class="token keyword">echo</span> <span class="token function">strcasecmp</span><span class="token punctuation">(</span><span class="token string double-quoted-string">"Hello world!"</span><span class="token punctuation">,</span><span class="token string double-quoted-string">"HELLO WORLD!"</span><span class="token punctuation">)</span><span class="token punctuation">;</span> <span class="token comment">// 两字符串相等</span> <span class="token keyword">echo</span> <span class="token function">strcasecmp</span><span class="token punctuation">(</span><span class="token string double-quoted-string">"Hello world!"</span><span class="token punctuation">,</span><span class="token string double-quoted-string">"HELLO"</span><span class="token punctuation">)</span><span class="token punctuation">;</span> <span class="token comment">// <i>string1</i> 大于 <i>string2</i></span> <span class="token keyword">echo</span> <span class="token function">strcasecmp</span><span class="token punctuation">(</span><span class="token string double-quoted-string">"Hello world!"</span><span class="token punctuation">,</span><span class="token string double-quoted-string">"HELLO WORLD! HELLO!"</span><span class="token punctuation">)</span><span class="token punctuation">;</span> <span class="token comment">// <i>string1</i> 小于 <i>string2</i></span> <span class="token delimiter important">?></span></span>