Hướng dẫn php cast to int
An int is a number of the set ℤ = {..., -2, -1, 0, 1, 2, ...}. See also:
Syntaxints can be specified in decimal (base 10), hexadecimal (base 16), octal (base 8) or binary (base 2) notation. The negation operator can be used to denote a negative int. To
use octal notation, precede the number with a As of PHP 7.4.0, integer literals may contain underscores ( Example #1 Integer literals
Formally, the structure for int literals is as of PHP 7.4.0 (previously, underscores have not been allowed): decimal : [1-9][0-9]*(_[0-9]+)* | 0 hexadecimal : 0[xX][0-9a-fA-F]+(_[0-9a-fA-F]+)* octal : 0[oO]?[0-7]+(_[0-7]+)* binary : 0[bB][01]+(_[01]+)* integer : decimal | hexadecimal | octal | binary The size of an int is platform-dependent, although a maximum value of about two billion is the usual value (that's 32 bits signed). 64-bit platforms usually have a maximum value of about 9E18. PHP does not support unsigned ints. int size can be determined using the constant Integer overflowIf PHP encounters a number beyond the bounds of the int type, it will be interpreted as a float instead. Also, an operation which results in a number beyond the bounds of the int type will return a float instead. Example #2 Integer overflow on a 32-bit system
Example #3 Integer overflow on a 64-bit system
There is no int division operator in PHP, to achieve this use the intdiv() function.
Converting to integer To
explicitly convert a value to int, use either the If a resource is converted to an int, then the result will be the unique resource number assigned to the resource by PHP at runtime. See also Type Juggling. From booleans From floating point numbersWhen converting from float to int, the number will be rounded towards zero. As of PHP 8.1.0, a deprecation notice is emitted when implicitly converting a non-integral float to int which loses precision.
If the float is beyond the boundaries of int (usually
Warning Never cast an unknown fraction to int, as this can sometimes lead to unexpected results.
See also the warning about float precision. From strings If the string is numeric or leading numeric then it will resolve to the corresponding integer value, otherwise it is converted to zero ( From NULL From other typesCaution The behaviour of converting to int is undefined for other types. Do not rely on any observed behaviour, as it can change without notice. php at richardneill dot org ¶ 9 years ago
d_n at NOSPAM dot Loryx dot com ¶ 15 years ago
dhairya lakhera ¶ 4 years ago
egwayjen at gmail dot com ¶ 4 years ago
ganlvtech at qq dot com ¶ 2 years ago
var_dump(0x7fffffffffffffff); // int(9223372036854775807) [email protected] ¶ 15 years ago
Anonymous ¶ 7 years ago
litbai ¶ 6 years ago
Anonymous ¶ 15 years ago
Anonymous ¶ 18 years ago
darkshire ¶ 14 years ago
kuzawinski dot marcin_NOSPAM at gmail dot com ¶ 2 years ago
(010); // int(8) NOT int(010) Jacek ¶ 15 years ago
eric ¶ 14 years ago
pere dot cil at wanadoo dot fr ¶ 11 years ago
wbcarts at juno dot com ¶ 13 years ago
itemToString() { 13453814063 at 163 dot com ¶ 4 years ago
dewi at dewimorgan dot com ¶ 7 years ago
jmw254 at cornell dot edu ¶ 16 years ago
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