rtrim
删除字符串末端的空白字符(或者其他字符)
从字符串右侧移除字符:
<span class="token php language-php"><span class="token delimiter important"><?php</span> <span class="token variable">$str</span> <span class="token operator">=</span> <span class="token string double-quoted-string">"Hello World!"</span><span class="token punctuation">;</span> <span class="token keyword">echo</span> <span class="token variable">$str</span> <span class="token operator">.</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">rtrim</span><span class="token punctuation">(</span><span class="token variable">$str</span><span class="token punctuation">,</span><span class="token string double-quoted-string">"World!"</span><span class="token punctuation">)</span><span class="token punctuation">;</span> <span class="token delimiter important">?></span></span>
移除字符串右侧的空格:
<span class="token php language-php"><span class="token delimiter important"><?php</span> <span class="token variable">$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 string double-quoted-string">"不使用 rtrim:"</span> <span class="token operator">.</span> <span class="token variable">$str</span><span class="token punctuation">;</span> <span class="token keyword">echo</span> <span class="token string double-quoted-string">"<br>"</span><span class="token punctuation">;</span> <span class="token keyword">echo</span> <span class="token string double-quoted-string">"使用 rtrim:"</span> <span class="token operator">.</span> <span class="token function">rtrim</span><span class="token punctuation">(</span><span class="token variable">$str</span><span class="token punctuation">)</span><span class="token punctuation">;</span> <span class="token delimiter important">?></span></span>
以上代码的 HTML 输出如下(查看源代码):
<span class="token operator"><</span><span class="token operator">!</span><span class="token constant">DOCTYPE</span> html<span class="token operator">></span> <span class="token operator"><</span>html<span class="token operator">></span> <span class="token operator"><</span>body<span class="token operator">></span> 不使用 rtrim:Hello World<span class="token operator">!</span> <span class="token operator"><</span>br<span class="token operator">></span>使用 rtrim:Hello World<span class="token operator">!</span> <span class="token operator"><</span><span class="token operator">/</span>body<span class="token operator">></span> <span class="token operator"><</span><span class="token operator">/</span>html<span class="token operator">></span>
以上代码的浏览器输出:
不使用 rtrim:Hello World! 使用 rtrim:Hello World!
移除字符串右侧的换行符(\n):
<span class="token php language-php"><span class="token delimiter important"><?php</span> <span class="token variable">$str</span> <span class="token operator">=</span> <span class="token string double-quoted-string">"Hello World!\n\n\n"</span><span class="token punctuation">;</span> <span class="token keyword">echo</span> <span class="token string double-quoted-string">"不使用 rtrim:"</span> <span class="token operator">.</span> <span class="token variable">$str</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 string double-quoted-string">"使用 rtrim:"</span> <span class="token operator">.</span> <span class="token function">rtrim</span><span class="token punctuation">(</span><span class="token variable">$str</span><span class="token punctuation">)</span><span class="token punctuation">;</span> <span class="token delimiter important">?></span></span>
以上代码的 HTML 输出如下(查看源代码):
<span class="token operator"><</span><span class="token operator">!</span><span class="token constant">DOCTYPE</span> html<span class="token operator">></span> <span class="token operator"><</span>html<span class="token operator">></span> <span class="token operator"><</span>body<span class="token operator">></span> 不使用 rtrim:Hello World<span class="token operator">!</span> <span class="token operator"><</span>br<span class="token operator">></span>使用 rtrim:Hello World<span class="token operator">!</span> <span class="token operator"><</span><span class="token operator">/</span>body<span class="token operator">></span> <span class="token operator"><</span><span class="token operator">/</span>html<span class="token operator">></span>
以上代码的浏览器输出:
不使用 rtrim:Hello World! 使用 rtrim:Hello World!