二十四橋明月夜24

　　驗證碼在表單實作越來越多了，但是用js的寫的驗證碼，總覺得不方便，所以學習了下php實作的驗證碼。

　　好吧，其實是沒有事情幹，但是又不想浪費時間，所以學習了下php實作驗證碼。正所謂，技多不壓身。而且，也可以封裝成函數，以後使用的時候也是很方便的，當然現在還沒有封裝。

　　現在來說說簡單的純數位驗證碼吧。

　　　　如果是初學者，建議按照我代碼的註釋 //數字  一步一步來。最簡單的方法，還是把整個程式碼複製走了。

　　　　新建一個captcha.php：

<?<span>php
    </span><span>//</span><span>10>设置session,必须处于脚本最顶部<span>session_start</span><span>();

    </span><span>$image</span> = imagecreatetruecolor(100, 30);        <span>//</span><span>1>设置验证码图片大小的函数
    //5>设置验证码颜色 imagecolorallocate(int im, int red, int green, int blue);</span><span>$bgcolor</span> = imagecolorallocate(<span>$image</span>,255,255,255); <span>//</span><span>#ffffff
    //6>区域填充 int imagefill(int im, int x, int y, int col)  (x,y) 所在的区域着色,col 表示欲涂上的颜色</span>    imagefill(<span>$image</span>, 0, 0, <span>$bgcolor</span><span>);
    </span><span>//</span><span>10>设置变量</span><span>$captcha_code</span> = ""<span>;
    </span><span>//</span><span>7>生成随机数字</span><span>for</span>(<span>$i</span>=0;<span>$i</span><4;<span>$i</span>++<span>){
        </span><span>//</span><span>设置字体大小</span><span>$fontsize</span> = 6<span>;        
        </span><span>//</span><span>设置字体颜色，随机颜色</span><span>$fontcolor</span> = imagecolorallocate(<span>$image</span>, <span>rand</span>(0,120),<span>rand</span>(0,120), <span>rand</span>(0,120));            <span>//</span><span>0-120深颜色
        //设置数字</span><span>$fontcontent</span> = <span>rand</span>(0,9<span>);
        </span><span>//</span><span>10>.=连续定义变量<span>$captcha_code</span> .= <span>$fontcontent</span><span>;    
        </span><span>//</span><span>设置坐标</span><span>$x</span> = (<span>$i</span>*100/4)+<span>rand</span>(5,10<span>);
        </span><span>$y</span> = <span>rand</span>(5,10<span>);

        imagestring(</span><span>$image</span>,<span>$fontsize</span>,<span>$x</span>,<span>$y</span>,<span>$fontcontent</span>,<span>$fontcolor</span><span>);
    }
    </span><span>//</span><span>10>存到session</span><span>$_SESSION</span>['authcode'] = <span>$captcha_code</span><span>;
    </span><span>//</span><span>8>增加干扰元素，设置雪花点</span><span>for</span>(<span>$i</span>=0;<span>$i</span><200;<span>$i</span>++<span>){
        </span><span>//</span><span>设置点的颜色，50-200颜色比数字浅，不干扰阅读</span><span>$pointcolor</span> = imagecolorallocate(<span>$image</span>,<span>rand</span>(50,200), <span>rand</span>(50,200), <span>rand</span>(50,200<span>));        
        </span><span>//</span><span>imagesetpixel &mdash; 画一个单一像素</span>        imagesetpixel(<span>$image</span>, <span>rand</span>(1,99), <span>rand</span>(1,29), <span>$pointcolor</span><span>);
    }
    </span><span>//</span><span>9>增加干扰元素，设置横线<span>for</span>(<span>$i</span>=0;<span>$i</span><4;<span>$i</span>++<span>){
        </span><span>//</span><span>设置线的颜色</span><span>$linecolor</span> = imagecolorallocate(<span>$image</span>,<span>rand</span>(80,220), <span>rand</span>(80,220),<span>rand</span>(80,220<span>));
        </span><span>//</span><span>设置线，两点一线</span>        imageline(<span>$image</span>,<span>rand</span>(1,99), <span>rand</span>(1,29),<span>rand</span>(1,99), <span>rand</span>(1,29),<span>$linecolor</span><span>);
    }

    </span><span>//</span><span>2>设置头部，image/png<span>header</span>('Content-Type: image/png'<span>);
    </span><span>//</span><span>3>imagepng() 建立png图形函数</span>    imagepng(<span>$image</span><span>);
    </span><span>//</span><span>4>imagedestroy() 结束图形函数  销毁$image</span>    imagedestroy(<span>$image</span>);

　〜接住頁提交的表單是到form. php的，所以還要有一個判斷的form.php程式碼：

<span><!</span><span>doctype html</span><span>></span><span><</span><span>html</span><span>></span><span><</span><span>head</span><span>></span><span><</span><span>meta </span><span>http-equiv</span><span>="Content-Type"</span><span> content</span><span>="text/html; charset=UTF-8"</span><span>></span><span><</span><span>title</span><span>></span>确认验证码<span></</span><span>title</span><span>></span><span></</span><span>head</span><span>></span><span><</span><span>body</span><span>></span><span><</span><span>form </span><span>method</span><span>="post"</span><span> action</span><span>="./form.php"</span><span>></span><span><</span><span>p</span><span>></span>验证码: <span><</span><span>img </span><span>id</span><span>="captcha_img"</span><span> border</span><span>='1' </span><span>src</span><span>='./captcha.php?r=<?php </span><span>echo rand(); ?</span><span>></span><span>' />
                </span><span><</span><span>a </span><span>href</span><span>="javascript:void(0)"</span><span> onclick</span><span>="document.getElementById('captcha_img').src='./captcha.php?r='+Math.random()"</span><span>></span>换一个?<span></</span><span>a</span><span>></span><span></</span><span>p</span><span>></span><span><</span><span>P</span><span>></span>请输入验证码:<span><</span><span>input </span><span>type</span><span>="text"</span><span> name</span><span>='authcode' </span><span>value</span><span>=''</span><span>/></</span><span>p</span><span>></span><span><</span><span>p</span><span>><</span><span>input </span><span>type</span><span>='submit' </span><span>value</span><span>='提交' </span><span>style</span><span>='padding:6px </span><span>5px;'</span><span>/></</span><span>p</span><span>></span><span></</span><span>body</span><span>></span><span></</span><span>html</span><span>></span>

　　顯示頁如下：

　　那麼，純數字的實現了，數字加英文的英文也應該不難了。要修改的程式碼   只是在

captcha.php

將//7>產生隨機數字 修改成  //7>產生隨機的字母和數字，如果你真的很可愛的數字就修改這幾個字就認為可以實現的話，那麼恭喜你，你永遠保持快樂。腦殘兒童歡樂多。

　　廢話不多說了，拉代碼吧。

<?<span>php
    </span><span>header</span>("Content-Type:text/html;charset=utf-8");            <span>//</span><span>设置头部信息
    //isset()检测变量是否设置</span><span>if</span>(<span>isset</span>(<span>$_REQUEST</span>['authcode'<span>])){
        </span><span>session_start</span><span>();
        </span><span>//</span><span>strtolower()小写函数</span><span>if</span>(<span>strtolower</span>(<span>$_REQUEST</span>['authcode'])== <span>$_SESSION</span>['authcode'<span>]){
            </span><span>//</span><span>跳转页面</span><span>echo</span> "<script language=\"javascript\">"<span>;
            </span><span>echo</span> "document.location=\"./form.php\""<span>;
            </span><span>echo</span> "</script>"<span>;
        }</span><span>else</span><span>{
            </span><span>//</span><span>提示以及跳转页面</span><span>echo</span> "<script language=\"javascript\">"<span>;
            </span><span>echo</span> "alert('输入错误!');"<span>;
            </span><span>echo</span> "document.location=\"./form.php\""<span>;
            </span><span>echo</span> "</script>"<span>;
        }
        </span><span>exit</span><span>();
    }</span>

　　其他的兩個頁面，不准要修改。

　　一般而言，現在就已經夠用了。但就像動漫一樣，總會有番外。

　　那麼，我們來個漢字的番外吧。其實我也準備將漢字的驗證碼放到我的畢業設計裡面，雖然現在很流行滑動驗證碼，但是本人畢竟不是專門學習js的。

　　而且，還可以和答辯的老師說，我們驗證碼不需要素材，連圖片也是生成的，用自己的知識裝13，也沒有設麼的。

<?<span>php
    </span><span>//</span><span>10>设置session,必须处于脚本最顶部<span>session_start</span><span>();

    </span><span>$image</span> = imagecreatetruecolor(100, 30);        <span>//</span><span>1>设置验证码图片大小的函数
    //5>设置验证码颜色 imagecolorallocate(int im, int red, int green, int blue);</span><span>$bgcolor</span> = imagecolorallocate(<span>$image</span>,255,255,255); <span>//</span><span>#ffffff
    //6>区域填充 int imagefill(int im, int x, int y, int col)  (x,y) 所在的区域着色,col 表示欲涂上的颜色</span>    imagefill(<span>$image</span>, 0, 0, <span>$bgcolor</span><span>);
    </span><span>//</span><span>10>设置变量</span><span>$captcha_code</span> = ""<span>;
    </span><span>//</span><span>7>生成随机的字母和数字</span><span>for</span>(<span>$i</span>=0;<span>$i</span><4;<span>$i</span>++<span>){
        </span><span>//</span><span>设置字体大小</span><span>$fontsize</span> = 8<span>;        
        </span><span>//</span><span>设置字体颜色，随机颜色</span><span>$fontcolor</span> = imagecolorallocate(<span>$image</span>, <span>rand</span>(0,120),<span>rand</span>(0,120), <span>rand</span>(0,120));            <span>//</span><span>0-120深颜色
        //设置需要随机取的值,去掉容易出错的值如0和o</span><span>$data</span> ='abcdefghigkmnpqrstuvwxy3456789'<span>;
        </span><span>//</span><span>取出值，字符串截取方法   strlen获取字符串长度</span><span>$fontcontent</span> = <span>substr</span>(<span>$data</span>, <span>rand</span>(0,<span>strlen</span>(<span>$data</span>)),1<span>);
        </span><span>//</span><span>10>.=连续定义变量<span>$captcha_code</span> .= <span>$fontcontent</span><span>;        
        </span><span>//</span><span>设置坐标</span><span>$x</span> = (<span>$i</span>*100/4)+<span>rand</span>(5,10<span>);
        </span><span>$y</span> = <span>rand</span>(5,10<span>);

        imagestring(</span><span>$image</span>,<span>$fontsize</span>,<span>$x</span>,<span>$y</span>,<span>$fontcontent</span>,<span>$fontcolor</span><span>);
    }
    </span><span>//</span><span>10>存到session</span><span>$_SESSION</span>['authcode'] = <span>$captcha_code</span><span>;
    </span><span>//</span><span>8>增加干扰元素，设置雪花点</span><span>for</span>(<span>$i</span>=0;<span>$i</span><200;<span>$i</span>++<span>){
        </span><span>//</span><span>设置点的颜色，50-200颜色比数字浅，不干扰阅读</span><span>$pointcolor</span> = imagecolorallocate(<span>$image</span>,<span>rand</span>(50,200), <span>rand</span>(50,200), <span>rand</span>(50,200<span>));        
        </span><span>//</span><span>imagesetpixel &mdash; 画一个单一像素</span>        imagesetpixel(<span>$image</span>, <span>rand</span>(1,99), <span>rand</span>(1,29), <span>$pointcolor</span><span>);
    }
    </span><span>//</span><span>9>增加干扰元素，设置横线<span>for</span>(<span>$i</span>=0;<span>$i</span><4;<span>$i</span>++<span>){
        </span><span>//</span><span>设置线的颜色</span><span>$linecolor</span> = imagecolorallocate(<span>$image</span>,<span>rand</span>(80,220), <span>rand</span>(80,220),<span>rand</span>(80,220<span>));
        </span><span>//</span><span>设置线，两点一线</span>        imageline(<span>$image</span>,<span>rand</span>(1,99), <span>rand</span>(1,29),<span>rand</span>(1,99), <span>rand</span>(1,29),<span>$linecolor</span><span>);
    }

    </span><span>//</span><span>2>设置头部，image/png<span>header</span>('Content-Type: image/png'<span>);
    </span><span>//</span><span>3>imagepng() 建立png图形函数</span>    imagepng(<span>$image</span><span>);
    </span><span>//</span><span>4>imagedestroy() 结束图形函数  销毁$image</span>    imagedestroy(<span>$image</span>);

　　其他的頁面也是不需要修改的。

　　效果圖如下：

以上就介紹了二十四橋明月夜24，包括了方面的內容，希望對PHP教程有興趣的朋友有幫助。