a simple php calculator
“simple calculator” makes use of the built-in PHP functions
is_numeric( ).
01 <?php
02
03 if(isset($_POST['act'])
04 && !empty($_POST['z1'])
05 && !empty($_POST['z2'])
06 && is_numeric($_POST['z1'])
07 && is_numeric($_POST['z2']))
08 {
09 if($_POST['act'] == 'add')
10 {
11 $calc = ($_POST['z1']+$_POST['z2']);
12 $op = '+';
13 }
14 if($_POST['act'] == 'sub')
15 {
16 $calc = ($_POST['z1']-$_POST['z2']);
17 $op = '-';
18 }
19 if($_POST['act'] == 'div')
20 {
21 $calc = ($_POST['z1']/$_POST['z2']);
22 $op = '/';
23 }
24 if($_POST['act'] == 'mul')
25 {
26 $calc = ($_POST['z1']*$_POST['z2']);
27 $op = '*';
28 }
29 if($_POST['act'] == 'pro')
30 {
31 $calc = (($_POST['z2']*$_POST['z1'])/100);
32 $op = '% of';
33 }
34 echo '
35 <p>'.$_POST['z1'].' '.$op.' '.$_POST['z2'].' = '.$calc.'</p>
36 <p><a href="./">try again</a></p>';
37
38 }else{
39 echo '
40 <form method="post" action="./">
41 <input type="text" name="z1" size="5" />
42 <select name="act">
43 <option value="add">[ + ]</option>
44 <option value="sub">[ - ]</option>
45 <option value="div">[ / ]</option>
46 <option value="mul">[ * ]</option>
47 <option value="pro">[ % ]</option>
48 </select>
49 <input type="text" name="z2" size="5" />
50 <input type="submit" name="doit" value="calculate" />
51 </form>';
52 }
53
54 ?>