如何设置TemplateField日历的选定字段？(How to set Selected field of TemplateField Calendar?)

 您可以检查小时数是否大于24小时，如果是，请添加一天，然后删除24小时。 
 
$actual='23:15';
$expected='25:45';

$day = 1;
list($hrs, $min) = explode(':', $expected);
if ($hrs > 24) { $day += 1; $hrs -= 24; }

$start_time = new DateTime("1970-01-01 $actual:00");
$time = $start_time->diff(new DateTime("1970-01-$day $hrs:$min:00"));

echo $time->format('%hh %Im');
 
 输出： 
 
2h 30m
 
 另请注意， ==用于比较，而不是分配。 
 
 如果有48小时或更长时间，你也可以用while()更改if ($hrs > 24) 。 
 
 
 编辑 
 
 正如@CollinD指出的那样，如果时间超过了一个月的天数，它就会失败。 这是另一个解决方案： 
 
$actual='23:15';
$expected='25:45';

list($hrs, $min) = explode(':', $actual);
$total1 = $min + $hrs * 60;

list($hrs, $min) = explode(':', $expected);
$diff = $min + $hrs * 60 - $total1;

$start_time = new DateTime();
$expected_time = new DateTime();
$expected_time->modify("+ $diff minutes");
$time = $start_time->diff($expected_time);

echo $time->format('%hh %Im');

You could check if the number of hours are greater than 24, and if so, add a day, and remove 24 hours.
 
$actual='23:15';
$expected='25:45';

$day = 1;
list($hrs, $min) = explode(':', $expected);
if ($hrs > 24) { $day += 1; $hrs -= 24; }

$start_time = new DateTime("1970-01-01 $actual:00");
$time = $start_time->diff(new DateTime("1970-01-$day $hrs:$min:00"));

echo $time->format('%hh %Im');
 
Output:
 
2h 30m
 
Please also note that == is used to compare, not to assign.
 
You can also change the if ($hrs > 24) by while(), if there is 48 hours or more.
 
 
edit
 
As pointed out by @CollinD, if the time exceed the number of days of the month, it will fail. Here is another solution:
 
$actual='23:15';
$expected='25:45';

list($hrs, $min) = explode(':', $actual);
$total1 = $min + $hrs * 60;

list($hrs, $min) = explode(':', $expected);
$diff = $min + $hrs * 60 - $total1;

$start_time = new DateTime();
$expected_time = new DateTime();
$expected_time->modify("+ $diff minutes");
$time = $start_time->diff($expected_time);

echo $time->format('%hh %Im');