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Rückspulen Sie den inneren Zeiger des Arrays zurück zu einem
Name:prev
Kategorie:Array
Programmiersprache:php
Kurzbeschreibung:Spulen Sie den inneren Zeiger des Arrays zurück zu einem.

Beispiel

Beispiel 1

Ausgabe der Werte des aktuellen Elements, des nächsten Elements und des vorherigen Elements im Array:

 <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">als nächstes</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>

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Beispiel 2

Demonstrieren Sie alle verwandten Methoden:

 <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">// Das aktuelle Element ist Bill</span>
<span class="token keyword">Echo</span> <span class="token function">als nächstes</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">// Das nächste Element von Bill ist 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">// Das aktuelle Element ist jetzt 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">// Das vorherige Element von Steve ist 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">// Das letzte Element ist 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">// Das Element vor David ist 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">// Das aktuelle aktuelle Element ist markiert</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">// Bewegen Sie den internen Zeiger auf das erste Element des Arrays, d. H. Bill</span>
<span class="token keyword">Echo</span> <span class="token function">als nächstes</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">// Das nächste Element von Bill ist Steve</span>

<span class="token function">print_r</span> <span class="token punctuation">(</span> <span class="token function">jeweils</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">// Gibt den Schlüsselnamen und den Schlüsselwert des aktuellen Elements (derzeit Steve) zurück und bewegt den internen Zeiger vorwärts</span>
<span class="token delimiter important">?></span>

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