php 高性能书写_PHP教程

$arr = array(
'attr1' => 1 ,
'attr2' => 1 ,
'attr3' => 1 ,
);
$startTime = microtime( true );
for( $i = 0 ; $i {
if( isset( $arr['attr1'] ) )
{

}
if( isset( $arr['attr2'] ) )
{

}
if( isset( $arr['attr3'] ) )
{

}
}
$endTime = microtime( true );
printf( "%d us.\n" , ( $endTime - $startTime ) * 1000000 );
$startTime = microtime( true );
for( $i = 0 ; $i {
foreach( $arr as $key => $value )
{
switch( $key )
{
case 'attr1':
break;
case 'attr2':
break;
case 'attr3':
break;
}
}
}
$endTime = microtime( true );
printf( "%d us.\n" , ( $endTime - $startTime ) * 1000000 );

foreach( $arr as $key => $value )
{
switch( $key )
{
case 'attr1':
break;
case 'attr2':
break;
case 'attr3':
break;
}
}

foreach( $arr as $key => $value )
{
if( $key == 'attr1' )
{

}
else if( $key == 'attr2' )
{

}
else if( $key == 'attr3' )
{

}
}