PHP SPL±ê×¼¿âÖ®SplFixedArrayʹÓÃʵÀý

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    ini_set('memory_limit','12800M');

    for($size = 10000; $size < 10000000; $size *= 4) {
      echo PHP_EOL . "Testing size: $size" . PHP_EOL;
      for($s = microtime(true), $container = Array(), $i = 0; $i < $size; $i++) $container[$i] = NULL;
      echo "Array(): " . (microtime(true) - $s) . PHP_EOL;

      for($s = microtime(true), $container = new SplFixedArray($size), $i = 0; $i < $size; $i++) $container[$i] = NULL;
      echo "SplArray(): " . (microtime(true) - $s) . PHP_EOL;
    }

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    Testing size: 10000
    Array(): 0.004000186920166
    SplArray(): 0.0019998550415039

    Testing size: 40000
    Array(): 0.017001152038574
    SplArray(): 0.0090007781982422

    Testing size: 160000
    Array(): 0.050002098083496
    SplArray(): 0.046003103256226

    Testing size: 640000
    Array(): 0.19701099395752
    SplArray(): 0.16700983047485

    Testing size: 2560000
    Array(): 0.75704312324524
    SplArray(): 0.67303895950317

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SplFixedArrayÀaÕªÒªÈçÏ£º

    SplFixedArray implements Iterator  , ArrayAccess  , Countable  {
      /* *½*¨ */
      public __construct ([ int $size = 0 ] )
      public int count ( void )
      public mixed current ( void )
      public static SplFixedArray fromArray ( array $array [, bool $save_indexes = true ] )
      public int getSize ( void )
      public int key ( void )
      public void next ( void )
      public bool offsetExists ( int $index )
      public mixed offsetGet ( int $index )
      public void offsetSet ( int $index , mixed $newval )
      public void offsetUnset ( int $index )
      public void rewind ( void )
      public int setSize ( int $size )
      public array toArray ( void )
      public bool valid ( void )
      public void __wakeup ( void )
    }

ʹÓÃSplFixedArray£º

    $arr = new SplFixedArray(4);
    $arr[0] = 'php';
    $arr[1] = 1;
    $arr[3] = 'python';

    //±eÀu£¬ $arr[2] Ϊnull
    foreach($arr as $v) {
      echo $v . PHP_EOL;
    }

    //»ñÈ¡Êý×e³¤¶È
    echo $arr->getSize(); //4

    //Ôo¼ÓÊý×e³¤¶È
    $arr->setSize(5);
    $arr[4] = 'new one';

    //²¶»ñÒi³£
    try{
      echo $arr[10];
    } catch (RuntimeException $e) {
      echo $e->getMessage();
    }