php表单计算器如何解决这个问题

Question

OK i am making a form that calculates line 1+ line 2 +*.01% then adds line 3+ line 4 then gives a total. I am having a problem with *.01 it works with just the first two but when i add the last two it drops one line if i take it out all four add fine.

<?php
if (count($_POST) > 0 && isset($_POST["calc15TextArea2"])){
    // add First and Second Numbers
    $sum = $_POST["indexEditbox1"] + $_POST["indexEditbox2"]*.01+ $_POST      ["calc15Editbox3"] + $_POST ["calc15Editbox4"];
    // their sum is diplayed as
    echo "Total is $ $sum";
}
?>

Answer 1

wrap all your post vars in intval() like eg intval($_POST['indexEditBox2'])

this function will get the integer value out of the string. (use the equivalent functions such as floatval() if they are not integers)

edit: Also try 0.01 in stead of .01. Given that this just is a wild hunch, I just might be that the .. is picked up as the concatenation operator.

so try:

    $sum = floatval( $_POST["indexEditbox1"] ) + floatval( $_POST["indexEditbox2"] ) * 0.01+ floatval( $_POST["calc15Editbox3"] ) + floatval( $_POST["calc15Editbox4"] ) ;

edit2: See the comments! multiplications and divisions take precedence over adding and subtracting.