php写简单计算器
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2024-02-27 12:36:33
...
<?php
echo <<<'FORM'
<form action="" method="post">
<input type="text" name="num1"/>
<select name="oper">
<option value="+">+</option>
<option value="-">-</option>
<option value="*">*</option>
<option value="/">/</option>
<option value="%">%</option>
</select>
<input type="text" name="num2"/>
<input type="submit" value="计算" />
</form>
FORM;
$a = (bool)$_POST['num1'];//判断是否为空，这里不能用isset
$b = (bool)$_POST['num2'];
$num1 = $_POST['num1']; //赋值
$num2 = $_POST['num2'];
$oper = $_POST['oper'];
$yan = is_numeric($_POST['num1']);//判断是否位数字
$zheng = is_numeric($_POST['num2']);
if($a&&$b ==true){ //是否为空
if($yan&&$zheng ==true){ //是否为数字
$dear = 0;
switch($oper){ //计算
case '+':
$dear = $num1+$num2;
break;
case '-':
$dear = $num1-$num2;
break;
case '*':
$dear = $num1*$num2;
break;
case '/':
$dear = $num1/$num2;
break;
case '%':
$dear = $num1%$num2;
break;
default:
echo '这个'.$oper.'不存在';
}
echo $num1.$oper.$num2.'='.$dear;
}else{
echo $num1.'或者'.$num2.'不是数字,请填写数字';
}
}else{
echo '<h2>不能为空</h2>';
}
功能一样
<!DOCTYPE html>
<html>
<head>
<title></title>
</head>
<body>
<form action="" method="post">
<input type="text" name="num1" value="<?php echo $_POST['num1']?>" />
<select name="oper">
<option value="+">+</option>
<option value="-">-</option>
<option value="*">*</option>
<option value="/">/</option>
<option value="%">%</option>
</select>
<input type="text" name="num2" value="<?php echo $_POST['num2']?>" />
<input type="submit" value="计算" />
</form>
</body>
<?php
if(((bool)$_POST['num1'])&&((bool)$_POST['num2']) ==true){ //是否为空
if((is_numeric($_POST['num1']))&&(is_numeric($_POST['num2'])) ==true){ //是否为数字
$dear = 0;
switch($_POST['oper']){ //计算
case '+':
$dear = $_POST['num1']+$_POST['num2'];
break;
case '-':
$dear = $_POST['num1']-$_POST['num2'];
break;
case '*':
$dear = $_POST['num1']*$_POST['num2'];
break;
case '/':
$dear = $_POST['num1']/$_POST['num2'];
break;
case '%':
$dear = $_POST['num1']%$_POST['num2'];
break;
default:
echo '这个'.$_POST['oper'].'不存在';
}
echo $_POST['num1'].$_POST['oper'].$_POST['num2'].'='.$dear;
}else{
echo $_POST['num1'].'或者'.$_POST['num2'].'不是数字,请填写数字';
}
}else{
echo '<h2>不能为空</h2>';
}
?>
</html>