php编写生成酷炫验证码 - 六月天空的芬芳

<span style="color: #008080;"> 1</span> <span style="color: #000000;">php
</span><span style="color: #008080;"> 2</span> <span style="color: #800080;">$im</span>=imagecreate(200,100<span style="color: #000000;">);//生成画布
</span><span style="color: #008080;"> 3</span> imagecolorallocate(<span style="color: #800080;">$im</span>,0,0,0<span style="color: #000000;">);//背景色
</span><span style="color: #008080;"> 4</span> <span style="color: #800080;">$white</span>=imagecolorallocate(<span style="color: #800080;">$im</span>,<span style="color: #008080;">rand</span>(0,255),<span style="color: #008080;">rand</span>(0,255),<span style="color: #008080;">rand</span>(0,255<span style="color: #000000;">));//生成随机颜色
</span><span style="color: #008080;"> 5</span> <span style="color: #0000ff;">for</span>(<span style="color: #800080;">$i</span>=0;<span style="color: #800080;">$i</span>$i++<span style="color: #000000;">)
</span><span style="color: #008080;"> 6</span> <span style="color: #000000;">{
</span><span style="color: #008080;"> 7</span>     imageline(<span style="color: #800080;">$im</span>,<span style="color: #008080;">rand</span>(0,200),<span style="color: #008080;">rand</span>(0,100),<span style="color: #008080;">rand</span>(0,200),<span style="color: #008080;">rand</span>(0,100),<span style="color: #800080;">$white</span><span style="color: #000000;">);//生成干扰线条元素
</span><span style="color: #008080;"> 8</span> <span style="color: #000000;">}
</span><span style="color: #008080;"> 9</span> <span style="color: #0000ff;">for</span>(<span style="color: #800080;">$i</span>=0;<span style="color: #800080;">$i</span>$i++<span style="color: #000000;">)
</span><span style="color: #008080;">10</span> <span style="color: #000000;">{
</span><span style="color: #008080;">11</span>     imagesetpixel(<span style="color: #800080;">$im</span>,<span style="color: #008080;">rand</span>(0,200),<span style="color: #008080;">rand</span>(0,100),<span style="color: #800080;">$white</span><span style="color: #000000;">);//生成干扰点元素
</span><span style="color: #008080;">12</span> <span style="color: #000000;">}
</span><span style="color: #008080;">13</span> <span style="color: #0000ff;">for</span>(<span style="color: #800080;">$i</span>=0,<span style="color: #800080;">$str</span>='';<span style="color: #800080;">$i</span>$i++<span style="color: #000000;">)//通过循环获得四个字符
</span><span style="color: #008080;">14</span> <span style="color: #000000;">{
</span><span style="color: #008080;">15</span>     <span style="color: #0000ff;">switch</span>(<span style="color: #008080;">rand</span>(1,3<span style="color: #000000;">))
</span><span style="color: #008080;">16</span> <span style="color: #000000;">    {
</span><span style="color: #008080;">17</span>         <span style="color: #0000ff;">case</span>'1':
<span style="color: #008080;">18</span>         <span style="color: #800080;">$ch</span>=<span style="color: #008080;">rand</span>(0,9<span style="color: #000000;">);
</span><span style="color: #008080;">19</span>         <span style="color: #0000ff;">break</span><span style="color: #000000;">; 
</span><span style="color: #008080;">20</span>         <span style="color: #0000ff;">case</span>'2':
<span style="color: #008080;">21</span>         <span style="color: #800080;">$ch</span>=<span style="color: #008080;">sprintf</span>('%c',<span style="color: #008080;">rand</span>(97,122<span style="color: #000000;">));
</span><span style="color: #008080;">22</span>         <span style="color: #0000ff;">break</span><span style="color: #000000;">;
</span><span style="color: #008080;">23</span>         <span style="color: #0000ff;">case</span>'3':
<span style="color: #008080;">24</span>         <span style="color: #800080;">$ch</span>=<span style="color: #008080;">sprintf</span>('%c',<span style="color: #008080;">rand</span>(65,90<span style="color: #000000;">));
</span><span style="color: #008080;">25</span>         <span style="color: #0000ff;">break</span><span style="color: #000000;">;
</span><span style="color: #008080;">26</span> <span style="color: #000000;">    }
</span><span style="color: #008080;">27</span>         <span style="color: #800080;">$str</span>.=<span style="color: #800080;">$ch</span><span style="color: #000000;">;
</span><span style="color: #008080;">28</span> 
<span style="color: #008080;">29</span> <span style="color: #000000;">}
</span><span style="color: #008080;">30</span> imagettftext(<span style="color: #800080;">$im</span>,32,<span style="color: #008080;">rand</span>(0,15),55,70,<span style="color: #800080;">$white</span>,'c.ttc',<span style="color: #800080;">$str</span><span style="color: #000000;">);//在画布上输出字符串
</span><span style="color: #008080;">31</span> <span style="color: #008080;">header</span>("Content-type:image/jpeg"<span style="color: #000000;">);
</span><span style="color: #008080;">32</span> imagejpeg(<span style="color: #800080;">$im</span><span style="color: #000000;">);
</span><span style="color: #008080;">33</span> imagedestroy(<span style="color: #800080;">$im</span><span style="color: #000000;">);
</span><span style="color: #008080;">34</span> ?>