php 简单的手工制作哈希功能

Posted 2021-05-04

<span style="color: #000000; font-weight: bold;">function</span> SimpleHash<span style="color: #66cc66;">&#40;</span><span style="color: #0000ff;">$str</span><span style="color: #66cc66;">&#41;</span><span style="color: #66cc66;">&#123;</span>    
&nbsp;
    <span style="color: #0000ff;">$n</span> = <span style="color: #cc66cc;">0</span>;
&nbsp;
    <span style="color: #808080; font-style: italic;">// The magic happens here:</span>
    <span style="color: #808080; font-style: italic;">// I just loop trough all letters and add the</span>
    <span style="color: #808080; font-style: italic;">// ASCII value to a integer variable. </span>
    <span style="color: #b1b100;">for</span> <span style="color: #66cc66;">&#40;</span><span style="color: #0000ff;">$c</span>=<span style="color: #cc66cc;">0</span>; <span style="color: #0000ff;">$c</span> &lt; <a href="http://www.php.net/strlen"><span style="color: #000066;">strlen</span></a><span style="color: #66cc66;">&#40;</span><span style="color: #0000ff;">$str</span><span style="color: #66cc66;">&#41;</span>; <span style="color: #0000ff;">$c</span>++<span style="color: #66cc66;">&#41;</span>
        <span style="color: #0000ff;">$n</span> += <a href="http://www.php.net/ord"><span style="color: #000066;">ord</span></a><span style="color: #66cc66;">&#40;</span><span style="color: #0000ff;">$str</span><span style="color: #66cc66;">&#91;</span><span style="color: #0000ff;">$c</span><span style="color: #66cc66;">&#93;</span><span style="color: #66cc66;">&#41;</span>;
&nbsp;
    <span style="color: #808080; font-style: italic;">// After we went trough all letters</span>
    <span style="color: #808080; font-style: italic;">// we have a number that represents the</span>
    <span style="color: #808080; font-style: italic;">// content of the string</span>
&nbsp;
    <span style="color: #b1b100;">return</span> <span style="color: #0000ff;">$n</span>;
<span style="color: #66cc66;">&#125;</span>