echo
輸出一個或多個字符串
輸出文本:
<span class="token php language-php"><span class="token delimiter important"><?php</span> <span class="token keyword">echo</span> <span class="token string double-quoted-string">"Hello world!"</span> <span class="token punctuation">;</span> <span class="token delimiter important">?></span></span>
把字符串變量($str)的值寫入輸出:
<span class="token php language-php"><span class="token delimiter important"><?php</span> <span class="token variable">$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">$str</span> <span class="token punctuation">;</span> <span class="token delimiter important">?></span></span>
把字符串變量($str)的值寫入輸出,包括HTML 標籤:
<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 punctuation">;</span> <span class="token keyword">echo</span> <span class="token string double-quoted-string">"<br>What a nice day!"</span> <span class="token punctuation">;</span> <span class="token delimiter important">?></span></span>
連接兩個字符串變量:
<span class="token php language-php"><span class="token delimiter important"><?php</span> <span class="token variable">$str1</span> <span class="token operator">=</span> <span class="token string double-quoted-string">"Hello world!"</span> <span class="token punctuation">;</span> <span class="token variable">$str2</span> <span class="token operator">=</span> <span class="token string double-quoted-string">"What a nice day!"</span> <span class="token punctuation">;</span> <span class="token keyword">echo</span> <span class="token variable">$str1</span> <span class="token operator">.</span> <span class="token string double-quoted-string">" "</span> <span class="token operator">.</span> <span class="token variable">$str2</span> <span class="token punctuation">;</span> <span class="token delimiter important">?></span></span>
把數組值寫入輸出:
<span class="token php language-php"><span class="token delimiter important"><?php</span> <span class="token variable">$age</span> <span class="token operator">=</span> <span class="token keyword">array</span> <span class="token punctuation">(</span> <span class="token string double-quoted-string">"Peter"</span> <span class="token operator">=></span> <span class="token string double-quoted-string">"35"</span> <span class="token punctuation">)</span> <span class="token punctuation">;</span> <span class="token keyword">echo</span> <span class="token string double-quoted-string">"Peter is "</span> <span class="token operator">.</span> <span class="token variable">$age</span> <span class="token punctuation">[</span> <span class="token string single-quoted-string">'Peter'</span> <span class="token punctuation">]</span> <span class="token operator">.</span> <span class="token string double-quoted-string">" years old."</span> <span class="token punctuation">;</span> <span class="token delimiter important">?></span></span>
把文本寫入輸出:
<span class="token php language-php"><span class="token delimiter important"><?php</span> <span class="token keyword">echo</span> <span class="token string double-quoted-string">"This text spans multiple lines."</span> <span class="token punctuation">;</span> <span class="token delimiter important">?></span></span>
如何使用多個參數:
<span class="token php language-php"><span class="token delimiter important"><?php</span> <span class="token keyword">echo</span> <span class="token string single-quoted-string">'This '</span> <span class="token punctuation">,</span> <span class="token string single-quoted-string">'string '</span> <span class="token punctuation">,</span> <span class="token string single-quoted-string">'was '</span> <span class="token punctuation">,</span> <span class="token string single-quoted-string">'made '</span> <span class="token punctuation">,</span> <span class="token string single-quoted-string">'with multiple parameters.'</span> <span class="token punctuation">;</span> <span class="token delimiter important">?></span></span>
單引號和雙引號的區別。單引號將輸出變量名稱,而不是值:
<span class="token php language-php"><span class="token delimiter important"><?php</span> <span class="token variable">$color</span> <span class="token operator">=</span> <span class="token string double-quoted-string">"red"</span> <span class="token punctuation">;</span> <span class="token keyword">echo</span> <span class="token string double-quoted-string">"Roses are <span class="token interpolation"><span class="token variable">$color</span></span> "</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 single-quoted-string">'Roses are $color'</span> <span class="token punctuation">;</span> <span class="token delimiter important">?></span></span>
簡化語法(只適用於short_open_tag 配置設置啟用的情況):
<span class="token php language-php"><span class="token delimiter important"><?php</span> <span class="token variable">$color</span> <span class="token operator">=</span> <span class="token string double-quoted-string">"red"</span> <span class="token punctuation">;</span> <span class="token delimiter important">?></span></span> <span class="token tag"><span class="token tag"><span class="token punctuation"><</span> p</span> <span class="token punctuation">></span></span> Roses are <span class="token php language-php"><span class="token delimiter important"><?=</span> <span class="token variable">$color</span> <span class="token delimiter important">?></span></span> <span class="token tag"><span class="token tag"><span class="token punctuation"></</span> p</span> <span class="token punctuation">></span></span>