用php简单实现加减乘除计算器_php技巧

header("content-type:text/html;charset=utf-8"); 
session_start(); 
?> 
 
 
 
 
 
 
 
 
 
 
$num1=$_POST['num1']; 
$num2=$_POST['num2']; 
$oper=$_POST['oper']; 
$rs=0; 
switch($oper){ 
case "+": 
$rs=$num1+$num2; 
break; 
case "-": 
$rs=$num1-$num2; 
break; 
case "*": 
$rs=$num1*$num2; 
break; 
case "/": 
$rs=$num1/$num2; 
break; 
default: echo "您输入的不正确"; 
} 
$_SESSION['rs']=$rs; 
echo '计算