PHP Question: Octal Values

15th April 2011 - 1 minute read time

Note: This post is over a year old and so the information contained here might be out of date. If you do spot something please leave a comment and I will endeavour to correct.

Question

If I assign and print a value like this:

$a = 012;
print $a;

I get back a value of '10', why?

Answer

This is because prefixing a number with a 0 in PHP forces the number to be interpreted as an octal value. However, it is stored internally as an integer value so when it is printed we get the integer value back. To get back the original octal value you could do something like this:

print base_convert($a, 10, 8);

Or even this:

print decoct($a);

Or even this:

print sprintf("%o", $a);

PHP

Comments

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in this case if you add first zero, php will interpreted the variable as octal number and convert this value to decimal number (?) ;p

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The title of the post gave this away, otherwise you might have got me with this one :)

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