php常用函数归纳

/**
 * 截取指定长度的字符
 * @param type $string  内容
 * @param type $start 开始
 * @param type $length 长度
 * @return type
 */
function ds_substing($string, $start=0,$length=80) {
    $string = strip_tags($string);
    $string = preg_replace(‘/\s/‘, ‘‘, $string);
    return mb_substr($string, $start, $length);
}

/**
 * 获取当前域名及根路径
 * @return string
 */
function base_url()
{
    $request = Request::instance();
    $subDir = str_replace(‘\\‘, ‘/‘, dirname($request->server(‘PHP_SELF‘)));
    return $request->scheme() . ‘://‘ . $request->host() . $subDir . ($subDir === ‘/‘ ? ‘‘ : ‘/‘);
}

/**
 * 写入日志   
 * @param string|array $values  
 * @param string $dir
 * @return bool|int
 */
function write_log($values, $dir)
{
    if (is_array($values))
        $values = print_r($values, true);
    // 日志内容
    $content = ‘[‘ . date(‘Y-m-d H:i:s‘) . ‘]‘ . PHP_EOL . $values . PHP_EOL . PHP_EOL;
    try {
        // 文件路径
        $filePath = $dir . ‘/logs/‘;
        // 路径不存在则创建
        !is_dir($filePath) && mkdir($filePath, 0755, true);
        // 写入文件
        return file_put_contents($filePath . date(‘Ymd‘) . ‘.log‘, $content, FILE_APPEND);
    } catch (\Exception $e) {
        return false;
    }
}

/**
 * curl请求指定url (get)
 * @param $url
 * @param array $data
 * @return mixed
 */
function curl($url, $data = [])
{
    // 处理get数据
    if (!empty($data)) {
        $url = $url . ‘?‘ . http_build_query($data);
    }
    $curl = curl_init();
    curl_setopt($curl, CURLOPT_URL, $url);
    curl_setopt($curl, CURLOPT_HEADER, false);
    curl_setopt($curl, CURLOPT_RETURNTRANSFER, 1);
    curl_setopt($curl, CURLOPT_SSL_VERIFYPEER, false);//这个是重点。
    $result = curl_exec($curl);
    curl_close($curl);
    return $result;
}

/**
 * curl请求指定url (post)  
 * @param $url
 * @param array $data
 * @return mixed
 */
function curlPost($url, $data = [])
{
    $ch = curl_init();
    curl_setopt($ch, CURLOPT_POST, 1);
    curl_setopt($ch, CURLOPT_HEADER, 0);
    curl_setopt($ch, CURLOPT_RETURNTRANSFER, 1);
    curl_setopt($ch, CURLOPT_URL, $url);
    curl_setopt($ch, CURLOPT_POSTFIELDS, $data);
    curl_setopt($ch, CURLOPT_SSL_VERIFYPEER, false);
    $result = curl_exec($ch);
    curl_close($ch);
    return $result;
}

/**
 * 多维数组合并
 * @param $array1
 * @param $array2
 * @return array
 */
function array_merge_multiple($array1, $array2)
{
    $merge = $array1 + $array2;
    $data = [];
    foreach ($merge as $key => $val) {
        if (
            isset($array1[$key])
            && is_array($array1[$key])
            && isset($array2[$key])
            && is_array($array2[$key])
        ) {
            $data[$key] = array_merge_multiple($array1[$key], $array2[$key]);
        } else {
            $data[$key] = isset($array2[$key]) ? $array2[$key] : $array1[$key];
        }
    }
    return $data;
}

/**
 * 二维数组排序
 * @param $arr
 * @param $keys
 * @param bool $desc
 * @return mixed
 */
function array_sort($arr, $keys, $desc = false)
{
    $key_value = $new_array = array();
    foreach ($arr as $k => $v) {
        $key_value[$k] = $v[$keys];
    }
    if ($desc) {
        arsort($key_value);
    } else {
        asort($key_value);
    }
    reset($key_value);
    foreach ($key_value as $k => $v) {
        $new_array[$k] = $arr[$k];
    }
    return $new_array;
}

/**
 * 数据导出到excel(csv文件)
 * @param $fileName
 * @param array $tileArray
 * @param array $dataArray
 */
function export_excel($fileName, $tileArray = [], $dataArray = [])
{
    ini_set(‘memory_limit‘, ‘512M‘);
    ini_set(‘max_execution_time‘, 0);
    ob_end_clean();
    ob_start();
    header("Content-Type: text/csv");
    header("Content-Disposition:filename=" . $fileName);
    $fp = fopen(‘php://output‘, ‘w‘);
    fwrite($fp, chr(0xEF) . chr(0xBB) . chr(0xBF));// 转码 防止乱码(比如微信昵称)
    fputcsv($fp, $tileArray);
    $index = 0;
    foreach ($dataArray as $item) {
        if ($index == 1000) {
            $index = 0;
            ob_flush();
            flush();
        }
        $index++;
        fputcsv($fp, $item);
    }
    ob_flush();
    flush();
    ob_end_clean();
}

//生成XML
function makeXML($data_array){
    $content=‘<?xml version="1.0" encoding="utf-8"?><urlset>‘;
    foreach($data_array as $data){
        $content.= create_item($data);
    }
    $content.=‘</urlset>‘;
    $fp=fopen(‘sitemap.xml‘,‘w+‘);
    fwrite($fp,$content);
    fclose($fp);
}