PHP 实用函数

阻止SQL注入

function clean($input)
{
    if (is_array($input))
    {
        foreach ($input as $key => $val)
         {
            $output[$key] = clean($val);
            // $output[$key] = $this->clean($val);
        }
    }
    else
    {
        $output = (string) $input;
        // if magic quotes is on then use strip slashes
        if (get_magic_quotes_gpc()) 
        {
            $output = stripslashes($output);
        }
        // $output = strip_tags($output);
        $output = htmlentities($output, ENT_QUOTES, 'UTF-8');
    }
// return the clean text
    return $output;
}

验证网址

function is_valid_url($url){
    $p1 ='/(http|https|ftp):\/\/[a-z0-9-]+(.[a-z0-9-]+)*(:[0-9]+)?(\/.*)?$/i';
    return preg_match($p1, $url);
}

验证邮箱地址

function is_validemail($email)
{
    $check = 0;
    if(filter_var($email,FILTER_VALIDATE_EMAIL))
    {
        $check = 1;
    }
    return $check;
}

验证ip地址

function is_valid_ip($ip){
    if (filter_var($ip, FILTER_VALIDATE_IP))
        return true;
    else
        return false;
}

获取用户的真实IP

function getRealIpAddr()  
{  
    if (!emptyempty($_SERVER['HTTP_CLIENT_IP']))  
    {  
        $ip=$_SERVER['HTTP_CLIENT_IP'];  
    }  
    elseif (!emptyempty($_SERVER['HTTP_X_FORWARDED_FOR']))  
        //to check ip is pass from proxy  
    {  
        $ip=$_SERVER['HTTP_X_FORWARDED_FOR'];  
    }  
    else  
    {  
        $ip=$_SERVER['REMOTE_ADDR'];  
    }  
    return $ip;  
}

把秒转换成天数，小时数和分钟

function secsToStr($secs)
{
    if($secs>=86400){$days=floor($secs/86400);$secs=$secs%86400;$r=$days.' day';if($days<>1){$r.='s';}if($secs>0){$r.=', ';}}
    if($secs>=3600){$hours=floor($secs/3600);$secs=$secs%3600;$r.=$hours.' hour';if($hours<>1){$r.='s';}if($secs>0){$r.=', ';}}
    if($secs>=60){$minutes=floor($secs/60);$secs=$secs%60;$r.=$minutes.' minute';if($minutes<>1){$r.='s';}if($secs>0){$r.=', ';}}
    $r.=$secs.' second';if($secs<>1){$r.='s';}
    return $r;
}

遍历目录

function list_files($dir)
{
    if(is_dir($dir))
    {
        if($handle = opendir($dir))
        {
            while(($file = readdir($handle)) !== false)
            {
                if($file != "." && $file != ".." && $file != "Thumbs.db"/*pesky windows, images..*/)
                {
                    echo '<a target="_blank" href="'.$dir.$file.'">'.$file.'</a>'."\n";
                }
            }
            closedir($handle);
        }
    }
}

检查网站是否宕机

function Visit($url)
{
    $agent = "Mozilla/4.0 (compatible; MSIE 5.01; Windows NT 5.0)";
    $ch=curl_init();
    curl_setopt ($ch, CURLOPT_URL,$url );
    curl_setopt($ch, CURLOPT_USERAGENT, $agent);
    curl_setopt ($ch, CURLOPT_RETURNTRANSFER, 1);
    curl_setopt ($ch,CURLOPT_VERBOSE,false);
    curl_setopt($ch, CURLOPT_TIMEOUT, 5);
    curl_setopt($ch,CURLOPT_SSL_VERIFYPEER, FALSE);
    curl_setopt($ch,CURLOPT_SSLVERSION,3);
    curl_setopt($ch,CURLOPT_SSL_VERIFYHOST, FALSE);
    $page=curl_exec($ch);
    //echo curl_error($ch);
    $httpcode = curl_getinfo($ch, CURLINFO_HTTP_CODE);
    curl_close($ch);
    if($httpcode>=200 && $httpcode<300) return true;
    else return false;
}
if (Visit("http://www.google.com"))
    echo "Website OK"."n";
else
    echo "Website DOWN";

简单的 php 防注入、防跨站 函数

function fn_safe($str_string) {
    //直接剔除
    $_arr_dangerChars = array(
        "|", ";", "$", "@", "+", "\t", "\r", "\n", ",", "(", ")", PHP_EOL //特殊字符
    );

    //正则剔除
    $_arr_dangerRegs = array(
        /* -------- 跨站 --------*/

        //html 标签
        "/<(script|frame|iframe|bgsound|link|object|applet|embed|blink|style|layer|ilayer|base|meta)\s+\S*>/i",

        //html 属性
        "/on(afterprint|beforeprint|beforeunload|error|haschange|load|message|offline|online|pagehide|pageshow|popstate|redo|resize|storage|undo|unload|blur|change|contextmenu|focus|formchange|forminput|input|invalid|reset|select|submit|keydown|keypress|keyup|click|dblclick|drag|dragend|dragenter|dragleave|dragover|dragstart|drop|mousedown|mousemove|mouseout|mouseover|mouseup|mousewheel|scroll|abort|canplay|canplaythrough|durationchange|emptied|ended|error|loadeddata|loadedmetadata|loadstart|pause|play|playing|progress|ratechange|readystatechange|seeked|seeking|stalled|suspend|timeupdate|volumechange|waiting)\s*=\s*(\"|')?\S*(\"|')?/i",

        //html 属性包含脚本
        "/\w+\s*=\s*(\"|')?(java|vb)script:\S*(\"|')?/i",

        //js 对象
        "/(document|location)\s*\.\s*\S*/i",

        //js 函数
        "/(eval|alert|prompt|msgbox)\s*\(.*\)/i",

        //css
        "/expression\s*:\s*\S*/i",

        /* -------- sql 注入 --------*/

        //显示 数据库 | 表 | 索引 | 字段
        "/show\s+(databases|tables|index|columns)/i",

        //创建 数据库 | 表 | 索引 | 视图 | 存储过程 | 存储过程
        "/create\s+(database|table|(unique\s+)?index|view|procedure|proc)/i",

        //更新 数据库 | 表
        "/alter\s+(database|table)/i",

        //丢弃 数据库 | 表 | 索引 | 视图 | 字段
        "/drop\s+(database|table|index|view|column)/i",

        //备份 数据库 | 日志
        "/backup\s+(database|log)/i",

        //初始化 表
        "/truncate\s+table/i",

        //替换 视图
        "/replace\s+view/i",

        //创建 | 更改 字段
        "/(add|change)\s+column/i",

        //选择 | 更新 | 删除 记录
        "/(select|update|delete)\s+\S*\s+from/i",

        //插入 记录 | 选择到文件
        "/insert\s+into/i",

        //sql 函数
        "/load_file\s*\(.*\)/i",

        //sql 其他
        "/(outfile|infile)\s+(\"|')?\S*(\"|')/i",
    );

    $_str_return = $str_string;
    //$_str_return = urlencode($_str_return);

    foreach ($_arr_dangerChars as $_key=>$_value) {
        $_str_return = str_ireplace($_value, "", $_str_return);
    }

    foreach ($_arr_dangerRegs as $_key=>$_value) {
        $_str_return = preg_replace($_value, "", $_str_return);
    }

    $_str_return = htmlentities($_str_return, ENT_QUOTES, "UTF-8", true);

    return $_str_return;
}