I'm projects table that users projects is saved in it and have start_time and finish_time and price,I give it as form that has this code:
<div class="form-group">
<input type="date" class="form-control" name="start_time" >
</div>
<div class="form-group">
<input type="date" class="form-control" name="finish_time" >
</div>
<div class="form-group">
<input type="text" class="form-control" name="price" >
</div>
Now,I Want subtract dates and if result be Negative Can multiply price and result,How I can do this?