织梦dedecms搜索添加验证码功能

验证码：<input type="text" name="validate"><img src="{dede:global.cfg_cmspath/}/include/vdimgck.php" align="absmiddle" onclick="this.src='{dede:global.cfg_cmspath/}/include/vdimgck.php?tag='+Math.random();" style="cursor:pointer;">

$mid = (isset($mid) && is_numeric($mid)) ? $mid : 0;

$validate = empty($validate) ? '' : strtolower(trim($validate)); $svali = strtolower(GetCkVdValue()); if($validate=='' || $validate != $svali) { ResetVdValue(); ShowMsg('验证码不正确!',$_SERVER["HTTP_REFERER"],0,1000); exit(); }