Kirk.Johnson@xxxxxxxxxxx wrote:
On Mon, 24 Mar 2008 13:10:17 -0600, Kirk.Johnson@xxxxxxxxxxx wrote:
Beware: round() apparently has changed its behavior from PHP 4. For
certain special numbers that seem to be multiples of 100,000, the
return
value is in exponential format, rather than the usual decimal format.
Some
of these special values are 1200000, 1400000, 2300000, which are
returned
as 1.2E+6, 1.4E+6, etc. You can generate your own list of these
special
numbers using this code:
<?php
for( $tmp = 0, $i = 0; $i < 100; $i++ ) {
$tmp += 100000;
echo round($tmp),"\n";
}
?>
I now have a list of 3 ways this change in behavior can bite you and
result in a failed transaction. In the examples below, assume that the
value passed to round() is '1200000', so that the value returned from
round() is '1.2E+6'.
1. When interpolating the value into xml, resulting in an xsd validation
error:
<?
$xml = '<AnnualIncome>' . round($income) . '</AnnualIncome>';
?>
2. When validating user input, resulting in a false positive:
<?
if(!ereg("^[0-9]{1,10}$", round($_POST['income']))) {
$errors .= "<li>Income should be whole dollars only (10 digits
max).</li>";
}
?>
For the above test, is there any reason you couldn't use is_numeric()
Looks like it would work in this case.
<?php
if ( ! is_numeric($_POST['income']) ) {
$errors .= "<li>Income should be whole dollars only ".
"(10 digits max).</li>";
}
?>
3. When interpolating a value into a stored procedure call, resulting in a
type mismatch between the value passed in and the database column data
type (which is likely decimal for a monetary value):
<?
$sql = "exec update_loan_financials
@application_id='$appID',
@total_debt=" . round($totalDebt);
?>
BTW, a previous poster pointed out that this is a change in behavior of
the float type, in general, not of the round() function, in particular.
If you care.
I don't. I just know I have broken code to fix and customers to apologize
to.
Kirk
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