php常用文件操作

#在需要查找的内容后一行新起一行插入内容    function insertAfterTarget($filePath, $insertCont, $target){        $result = null;        $fileCont = file_get_contents($filePath);        $targetIndex = strpos($fileCont, $target); #查找目标字符串的坐标        if ($targetIndex !== false) {            #找到target的后一个换行符            $chLineIndex = strpos(substr($fileCont, $targetIndex), "\n") + $targetIndex;            if ($chLineIndex !== false) {                #插入需要插入的内容                $result = substr($fileCont, 0, $chLineIndex + 1) . $insertCont . "\n" . substr($fileCont, $chLineIndex + 1);                $fp = fopen($filePath, "w+");                fwrite($fp, $result);                fclose($fp);            }        }    }#删除内容所在的某一行    function delTargetLine($filePath, $target){        $result = null;        $fileCont = file_get_contents($filePath);        $targetIndex = strpos($fileCont, $target); #查找目标字符串的坐标        if ($targetIndex !== false) {            #找到target的前一个换行符            $preChLineIndex = strrpos(substr($fileCont, 0, $targetIndex + 1), "\n");            #找到target的后一个换行符            $AfterChLineIndex = strpos(substr($fileCont, $targetIndex), "\n") + $targetIndex;            if ($preChLineIndex !== false && $AfterChLineIndex !== false) {                #重新写入删掉指定行后的内容                $result = substr($fileCont, 0, $preChLineIndex + 1) . substr($fileCont, $AfterChLineIndex + 1);                $fp = fopen($filePath, "w+");                fwrite($fp, $result);                fclose($fp);            }        }    }#获取某段内容的行号    /**     * @param $filePath     * @param $target   待查找字段     * @param bool $first   是否再匹配到第一个字段后退出     * @return array     */    function getLineNum($filePath, $target, $first = false){        $fp = fopen($filePath, "r");        $lineNumArr = array();        $lineNum = 0;        while (!feof($fp)) {            $lineNum++;            $lineCont = fgets($fp);            if (strstr($lineCont, $target)) {                if($first) {                    return $lineNum;                } else {                    $lineNumArr[] = $lineNum;                }            }        }        return $lineNumArr;    }