php读取大文件的方法

$starttime = microtime_float();
ini_set(‘memory_limit‘,‘-1‘);
$file = "testfile.txt";
$data = file($file);
$line = count($data);//总行数
$lastLine = $data[count($data)-1]; //最后一行

echo count($data);
echo $endtime = microtime_float();

function microtime_float(){
    list($usec,$sec) = explode(" ",microtime());
    return (float($usec) + float($sec))
}

<?php
$file = fopen("testfile.txt","r");
 while(!feof($file))
 {
     echo fgets($file);
 }
 fclose($file);

<?php
try{
    foreach( new SplFileObject(‘testfile.txt‘) as $line)
    echo $line.‘<br />‘;
}catch (Exception $e){
    echo $e->getMessage();
}