PHP comparison operator analysis explanation

If you compare an integer and a string, the string will be converted to an integer. If comparing two numeric strings, compare as integers. This rule also applies to switch statements

1, for arrays
$a=array(1,2,3,6);
$b=array(1,2,3,6,8);
echo "\n";
var_dump( $a>$b);
var_dump( $a==$b );
var_dump( $a<$b);

Result:
boolean false
boolean false
boolean true

ps: with fewer members The array is smaller

$a=array(1,2,3,6,9);
$b=array(1,2,3,6,8);
echo "\ n";
var_dump( $a>$b);
var_dump( $a==$b);
var_dump( $a<$b);
boolean true
boolean false
boolean false

ps: Compare values ​​one by one

$a=array(1,2,3,6,'b'=>3);
$b=array(1,2,3,6,8);
echo "\n";
var_dump( $a>$b);
var_dump( $a==$ b);
var_dump( $a<$b);
boolean false
boolean false
boolean false

ps: If the key in operand 1 does not exist In operand 2, the arrays cannot be compared, and false is returned.

2. Compare bool or null with other types

var_dump((bool)(null));//boolean false//null is converted to false when bool;

null and other types are converted to bool and then compared, and FALSE < TRUE

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