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將數組的內部指針倒回一位
中文(繁體)
中文(繁體)
輸出數組中的當前元素、下一個元素和上一個元素的值：
<span class="token php language-php"><span class="token delimiter important"><?php</span> <span class="token variable">$people</span> <span class="token operator">=</span> <span class="token keyword">array</span> <span class="token punctuation">(</span> <span class="token string double-quoted-string">"Bill"</span> <span class="token punctuation">,</span> <span class="token string double-quoted-string">"Steve"</span> <span class="token punctuation">,</span> <span class="token string double-quoted-string">"Mark"</span> <span class="token punctuation">,</span> <span class="token string double-quoted-string">"David"</span> <span class="token punctuation">)</span> <span class="token punctuation">;</span> <span class="token keyword">echo</span> <span class="token function">current</span> <span class="token punctuation">(</span> <span class="token variable">$people</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 keyword">echo</span> <span class="token function">next</span> <span class="token punctuation">(</span> <span class="token variable">$people</span> <span class="token punctuation">)</span> <span class="token operator">.</span> <span class="token string double-quoted-string">"<br>"</span> <span class="token punctuation">;</span> <span class="token keyword">echo</span><span class="token function"></span></span><mark> <span class="token function">prev</span> <span class="token punctuation">(</span> <span class="token variable">$people</span> <span class="token punctuation">)</span></mark><span class="token punctuation"></span> <span class="token punctuation">;</span> <span class="token delimiter important">?></span>
演示所有相關的方法：
<span class="token php language-php"><span class="token delimiter important"><?php</span> <span class="token variable">$people</span> <span class="token operator">=</span> <span class="token keyword">array</span> <span class="token punctuation">(</span> <span class="token string double-quoted-string">"Bill"</span> <span class="token punctuation">,</span> <span class="token string double-quoted-string">"Steve"</span> <span class="token punctuation">,</span> <span class="token string double-quoted-string">"Mark"</span> <span class="token punctuation">,</span> <span class="token string double-quoted-string">"David"</span> <span class="token punctuation">)</span> <span class="token punctuation">;</span> <span class="token keyword">echo</span> <span class="token function">current</span> <span class="token punctuation">(</span> <span class="token variable">$people</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 comment">// 當前元素是Bill</span> <span class="token keyword">echo</span> <span class="token function">next</span> <span class="token punctuation">(</span> <span class="token variable">$people</span> <span class="token punctuation">)</span> <span class="token operator">.</span> <span class="token string double-quoted-string">"<br>"</span> <span class="token punctuation">;</span> <span class="token comment">// Bill 的下一個元素是Steve</span> <span class="token keyword">echo</span> <span class="token function">current</span> <span class="token punctuation">(</span> <span class="token variable">$people</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 comment">// 現在當前元素是Steve</span> <span class="token keyword">echo</span><span class="token function"></span></span><mark> <span class="token function">prev</span> <span class="token punctuation">(</span> <span class="token variable">$people</span> <span class="token punctuation">)</span></mark><span class="token punctuation"></span> <span class="token operator">.</span> <span class="token string double-quoted-string">"<br>"</span> <span class="token punctuation">;</span> <span class="token comment">// Steve 的上一個元素是Bill</span> <span class="token keyword">echo</span> <span class="token function">end</span> <span class="token punctuation">(</span> <span class="token variable">$people</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 comment">// 最後一個元素是David</span> <span class="token keyword">echo</span><span class="token function"></span><mark> <span class="token function">prev</span> <span class="token punctuation">(</span> <span class="token variable">$people</span> <span class="token punctuation">)</span></mark><span class="token punctuation"></span> <span class="token operator">.</span> <span class="token string double-quoted-string">"<br>"</span> <span class="token punctuation">;</span> <span class="token comment">// David 之前的元素是Mark</span> <span class="token keyword">echo</span> <span class="token function">current</span> <span class="token punctuation">(</span> <span class="token variable">$people</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 comment">// 目前的當前元素是Mark</span> <span class="token keyword">echo</span> <span class="token function">reset</span> <span class="token punctuation">(</span> <span class="token variable">$people</span> <span class="token punctuation">)</span> <span class="token operator">.</span> <span class="token string double-quoted-string">"<br>"</span> <span class="token punctuation">;</span> <span class="token comment">// 把內部指針移動到數組的首個元素，即Bill</span> <span class="token keyword">echo</span> <span class="token function">next</span> <span class="token punctuation">(</span> <span class="token variable">$people</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 comment">// Bill 的下一個元素是Steve</span> <span class="token function">print_r</span> <span class="token punctuation">(</span> <span class="token function">each</span> <span class="token punctuation">(</span> <span class="token variable">$people</span> <span class="token punctuation">)</span> <span class="token punctuation">)</span> <span class="token punctuation">;</span> <span class="token comment">// 返回當前元素的鍵名和鍵值（目前是Steve），並向前移動內部指針</span> <span class="token delimiter important">?></span>
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