PHP实战之WEB计算器
<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">
<html xmlns="http://www.w3.org/1999/xhtml" xml:lang="en">
<head>
<meta http-equiv="Content-Type" content="text/html;charset=UTF-8" />
<title>Document</title>
</head>
<body>
<form action="#" method="post">
<input type="text" name="num1"/>
<select name="op">
<option value="+" >+</option>
<option value="-" >-</option>
<option value="*" >*</option>
<option value="/" >/</option>
</select>
<input type="text" name="num2" />
<input type="submit" name="jisuan" value="计算" / >
</form>
</body>
</html>
<?php
$num1=$_POST['num1'];
$num2=$_POST['num2'];
$op=$_POST['op'];
$jisuan=$_POST['jisuan'];
if(isset($jisuan)){
if(is_numeric($num1)&&is_numeric($num2)){
if($op=='+'){
$num=$num1+$num2;
}elseif($op=='-'){
$num=$num1-$num2;
}elseif($op=='*'){
$num=$num1*$num2;
}elseif($op=='/'){
if($num2!=0){
$num=$num1/$num2;
}else{
echo 'num2不能为0';
die();
}
}else{
echo '非法数据';
};
echo "{$num1}{$op}{$num2}={$num}";
}else{
echo '非法数字';
}
}else{
echo '请输入数字';
}
?>