有时当我使用这个函数(日期)的输入时，我得到垃圾，描述:
<?php
function optimized_subscription_total($active_sub_time,$arr_sub_values)
{
// This function takes a row from the DB where prices for each period of time usage is listed. there are prices for 1 month, 3 months,6 and 12 months.
// when the user has subscribed for 12 months, and the user asks for a refund, after they used 9 months and 6 days for example, the system treats the refund as if they subscribed for (in months) COST_6 + COST_3 + (COST_1/30)*6
// the result of the function is then subtracted from the amount they actually paid and is considered the refund.
// $arr_sub_values is the associative row from the DB, containing the prices
// $active_sub_time is measured in months and is a double
$result=0;
if(($active_sub_time-6)>=0)
{
$active_sub_time-=6;
$result+=($arr_sub_values['COST_6']);
}
if(($active_sub_time-3)>=0)
{
$active_sub_time-=3;
$result+=($arr_sub_values['COST_3']);
}
while(($active_sub_time-1)>=0)
{
$active_sub_time-=1;
$result+=($arr_sub_values['COST_1']);
}
if($active_sub_time>0)
$result+=($active_sub_time)*($arr_sub_values['COST_1']);
return $result;
}
$datetime1 = date_create('2009-12-11');
$datetime2 = date_create('2010-11-09');
$interval = date_diff($datetime1, $datetime2);
$num_of_months = ($interval->format('%y'))*12+($interval->format('%m'))+($interval->format('%a'))/30;
echo "<br />";
$v = array('COST_1'=>'3.99','COST_3'=>'9.99','COST_6'=>'15.99','COST_12'=>'25.99');
echo "OPT value for $num_of_months months=" . optimized_subscription_total($num_of_months, $v);
?>
我不明白为什么我得到:
OPT value for 10 months=M.97
作为这里的结果。我想我需要一个浮点数，不是吗?
我期待函数的结果应该是"10个月的OPT值=29.97"，因为它应该采取COST_6 + COST_3 + COST_1…但我得到的是奇怪的M.97，有时是POKHHHG.97
下面是相同的函数:
function optimized_subscription_total($active_sub_time,$arr_subscription_values)
{
$result=0;
while(($active_sub_time-12)>=0)
{
$active_sub_time-=12;
$result+=($arr_subscription_values['COST_12']);
}
if(($active_sub_time-6)>=0)
{
$active_sub_time-=6;
$result+=($arr_subscription_values['COST_6']);
}
if(($active_sub_time-3)>=0)
{
$active_sub_time-=3;
$result+=($arr_subscription_values['COST_3']);
}
while(($active_sub_time-1)>=0)
{
$active_sub_time-=1;
$result+=($arr_subscription_values['COST_1']);
}
if($active_sub_time>0)
$result+=($active_sub_time)*($arr_subscription_values['COST_1']);
return $result;
}
我只希望这不会坏。但谁能告诉我第一个版本哪里出了问题?那会是什么呢?
edit:我在刷新页面大约10次后出现了这个错误，现在我得到了一个奇怪的I.004谢谢! !
你想要完成的事情很简单，假设一个月有31天(事实并非如此)。DateTime::diff()假定是这样的。你可能想把2月的28天当作一个完整的月，但是?
<?php
function calculateRealCost($started, $ended) {
// month values
$_month = array(
12 => 25.99,
6 => 15.99,
3 => 9.99,
1 => 3.99
);
// assuming a median of 30 days per month.
// it's closer to 30.4 days per month, though.
$_day = $_month[1] / 30;
$price = 0;
// identify the time span
$started = $started instanceof DateTime ? $started : new DateTime($started);
$ended = $ended instanceof DateTime ? $ended : new DateTime($ended);
// you should note that diff() treat's the last day inclusive, so it may be "a day short"
$diff = $started->diff($ended);
// add years (12 months)
$price += $_month[12] * $diff->y;
// add months
$months = $diff->m;
foreach ($_month as $m => $v) {
while ($m <= $months) {
$price += $v;
$months -= $m;
}
}
// add days
$price += $_day * $diff->d;
// return rounded to two decimals
return round($price, 2);
}
$test = array(
// 0 years 10 months, 29 days
// 15.99 + 9.99 + 3.99 + (0.133 * 29)
array('start' => "2009-12-11", 'end' => "2010-11-09", 'cost' => 33.83),
// 1 years 10 months, 27 days
// 25.99 + 15.99 + 9.99 + 3.99 + (0.133 * 27)
array('start' => "2009-12-11", 'end' => "2011-11-07", 'cost' => 59.55),
// 0 years 0 months, 28 days
// (0.133 * 28)
array('start' => "2011-02-01", 'end' => "2011-03-01", 'cost' => 3.72),
// 0 years 0 months, 29 days
// (0.133 * 29)
array('start' => "2012-02-01", 'end' => "2012-03-01", 'cost' => 3.86),
// 0 years 1 months, 29 days
// 3.99 + (0.133 * 29)
array('start' => "2011-09-01", 'end' => "2011-10-31", 'cost' => 7.85),
);
foreach ($test as $t) {
$res = calculateRealCost($t['start'], $t['end']);
if ($res != $t['cost']) {
echo "{$t['start']} to {$t['end']} expected {$t['cost']} but got {$res}'n";
}
}