Question

具有以下值：

$a[0] = "4:00:00 am"
$b[0] = "8:00:00 am"
$c[0] = "9:00:00 am"
$d[0] = "1:22:00 pm"

为什么第二个if语句会将-8值写入数据库？第一个if语句产生适当的4小时值，但不是第二个。是因为am / pm变化还是什么？

if (!$a[0]=="" AND !$b[0]=="") {
   $start = explode(':', $a[0]);
   $end = explode(':', $b[0]);
   $total_hours = $end[0] - $start[0] - ($end[1] < $start[1]);
   mysqli_query($con,"UPDATE timeclock SET daily_hours='$total_hours' WHERE idex='$data[idex]' AND date='$date' AND status='slunch'");
}

if (!$c[0]=="" AND !$d[0]=="") {
   $start = explode(':', $c[0]);
   $end = explode(':', $d[0]);
   $total_hours = $end[0] - $start[0] - ($end[1] < $start[1]);
   mysqli_query($con,"UPDATE timeclock SET daily_hours='$total_hours' WHERE idex='$data[idex]' AND date='$date' AND status='ework'");
}

Answer 1

因为下午1点到9点等同于1 - 9，即-8。您需要将PM时间转换为24小时制，例如

1pm -> 13
9am -> 9

13 - 9 = 4

Answer 2

您的代码完全按预期工作。只是你在不将其转换为24小时格式的情况下减去时间。

您可以使用date()进行转换，如下所示：

$time_in_24 = date("H:i", strtotime("1:22:00 pm")); // 13:22

将您的代码更改为：

$a[0] = date("H:i", strtotime("4:00:00 am"));  
$b[0] = date("H:i", strtotime("8:00:00 am"));  
$c[0] = date("H:i", strtotime("9:00:00 am"));  
$d[0] = date("H:i", strtotime("1:22:00 pm"));

那应该解决它。

键盘：http://codepad.org/jsltDXK0

Answer 3

$a[0] = "4:00:00 am";
$b[0] = "8:00:00 am";
$c[0] = "9:00:00 am";
$d[0] = "1:22:00 pm";
if (!$a[0]=="" AND !$b[0]=="") {
   $start = convert($a[0]);
   $end = conver($b[0]);
   $total_hours = $end[0] - $start[0] - ($end[1] < $start[1]);
   mysqli_query($con,"UPDATE timeclock SET daily_hours='$total_hours' WHERE idex='$data[idex]' AND date='$date' AND status='slunch'");
}

if (!$c[0]=="" AND !$d[0]=="") {
   $start = convert($c[0]);
   $end = convert($d[0]);
   $total_hours = $end[0] - $start[0] - ($end[1] < $start[1]);
   mysqli_query($con,"UPDATE timeclock SET daily_hours='$total_hours' WHERE idex='$data[idex]' AND date='$date' AND status='ework'");
}

function convert($hour){
    $m = strtolower(substr($hour, -2));//am or pm
    $hr = array_slice(explode(':', $hour), 0, 2);
    if ($m == 'pm') $hr[0] += 12;
    return $hr;
}

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3 个答案: