Working with PHP Octals and String conversions
I'm working with a database that has a bunch of serial numbers that are prefixed with leading 0's. 开发者_运维百科
So a serial number can look like 00032432 or 56332432.
Problem is with PHP I don't understand how the conversion system with octals works.
A specific example is that I'm trying to convert and compare all of these integer based numbers with strings.
Is it possible to convert an octal, such as 00234 to a string like "00234" so that I can compare it?
edit - adding a specific example. I would like to be able to run str functions on the serial like below.
$serial = 00032432; // coming from DB
if(substr($serial, 0, 1) == '0') {
// do something
}
When you convert with (string) $number
, you always get a string in decimal base, it doesn't matter if you write the number in octal mode or in decimal mode, an int is an int and it has not itself a base. It's his string representation that have to be interpreted with a base.
You can get the octal string representation of a number in this way:
$str = base_convert((string) 00032432, 10, 8);
or giving the number in decimal rep:
$str = base_convert((string) 13594, 10, 8);
or, more concisely but less clearly:
$str = base_convert(00032432, 10, 8);
$str = base_convert(13594, 10, 8);
In the last the string conversion is made implicitly. The examples give all as result $str = "32432".
base_convert converts a string representation of a number from a base to another
If you want also the zeros in your string, you can add them with simple math.
Hope this can help you.
To convert an octal to a string, cast it:
$str = (string) 00032432;
You can convert between octal and decimal with the functions octdec and decoct
<?php
echo octdec('77') . "\n";
echo octdec(decoct(45));
?>
http://uk.php.net/manual/en/function.octdec.php
$str = sprintf('%o', $octal_value);
$serial = 00032432; //here you have an octal number
$serial= strval($serial); //now you have a string
if ($serial[0]=="0") {
//do something
}
Everything from the database is automatically a string. Integers are strings, dates are strings, dogs are strings.
If you are doing something weird, convert anything to a string by: $a = (string) 12;
精彩评论