PHP implements online calculator function
This article mainly introduces the simple online calculator function implemented in PHP, involving skills related to PHP numerical operations and form operations. Friends in need can refer to it
The details are as follows:
<html>
<head>
<meta http-equiv="content-type" content="text/html; charset=utf8">
<title>简单的计算器(www.jb51.net)</title>
</head>
<body>
<?php
//如果用户单击了计算按钮才存在表单变量，才能接收表单数据和对数据进行验证
//以下if语句判断是否将表单中的两个操作数提交到本页面，如果没有则不执行
if(isset($_POST["num1"]) && isset($_POST["num2"])){
if(empty($_POST["num1"])){
//如果第一个第一个操作数为空输出错误信息，并停止计算
echo "<font color='red'>第一个操作数不能为空</font>";
unset($_POST["sub"]);
//取消表单中的提交变量，后面计算判断时将不执行
}
if(empty($_POST["num2"])){
//如果第二个第一个操作数为空输出错误信息，并停止计算
echo "<font color='red'>第二个操作数不能为空</font>";
unset($_POST["sub"]);
//取消表单中的提交变量，后面计算判断时将不执行
}
$oper=$_POST["oper"];
//获取操作符号
$num1=$_POST["num1"];
//获取第一个操作数
$num2=$_POST["num2"];
//获取第二个操作数
if($oper == "/"){
if($num2 == 0){
echo "<font color='red'>0不能作为除数使用</font>";
unset($_POST["sub"]);
}
}
}
?>
<!--以HTML表格的形式输出计算器的用户操作界面-->
<table border="1" align="center" width="400">
<form action="" method="post"> <!--使用POST方法提交给本页面-->
<caption><h2>简单的计算器</h2></caption>
<tr>
<td><input type="text" size="10" name="num1" value="<?php if(!empty($num1)){echo $num1;}?>"></td>
<td>
<select name="oper">
<option value="+" <?php if($oper == "+"){echo "selected";}?>>+</option>
<option value="-" <?php if($oper == "-"){echo "selected";}?>>-</option>
<option value="*" <?php if($oper == "*"){echo "selected";}?>>*</option>
<option value="/" <?php if($oper == "/"){echo "selected";}?>>/</option>
</select>
</td>
<td><input type="text" size="10" name="num2" value="<?php if(!empty($num2)){echo $num2;}?>"></td>
<td><input type="submit" name="sub" value="计算"></td>
</tr>
<?php
/**通过表单传过来的$_POST["sub]，判断是否单击了计算按钮
来决定以下计算是否执行以及是否输出计算结果**/
if(isset($_POST["sub"]) && !empty($_POST["sub"])){
$sum = 0; //声明一个存放计算结果的变量，初始值为0
echo $sum;
//使用switch语句，通过表单选择的操作符来决定执行哪种运算
switch($oper){
case "+":
$sum = $num1+$num2;
break;
case "-":
$sum = $num1-$num2;
break;
case "*":
$sum = $num1*$num2;
break;
case "/":
$sum = $num1/$num2;
break;
}
//以下的三行是在表格的新行中输出计算结果
echo "<tr><td colspan='4' align='center'>";
echo "计算结果:$num1 $oper $num2 = $sum";
echo "</td></tr>";
}
?>
</form>
</table>
</body>
</html>Related recommendations:
PHP implementationOnline calculation Detailed explanation of the tool function sample code
Use php mysql to make a powerful Online calculation device_PHP tutorial
##phpOnline calculation device Implementation
The above is the detailed content of PHP implements online calculator function. For more information, please follow other related articles on the PHP Chinese website!
Hot AI Tools
Undresser.AI Undress
AI-powered app for creating realistic nude photos
AI Clothes Remover
Online AI tool for removing clothes from photos.
Undress AI Tool
Undress images for free
Clothoff.io
AI clothes remover
AI Hentai Generator
Generate AI Hentai for free.
Hot Article
Hot Tools
Notepad++7.3.1
Easy-to-use and free code editor
SublimeText3 Chinese version
Chinese version, very easy to use
Zend Studio 13.0.1
Powerful PHP integrated development environment
Dreamweaver CS6
Visual web development tools
SublimeText3 Mac version
God-level code editing software (SublimeText3)
Hot Topics
CakePHP Project Configuration
Sep 10, 2024 pm 05:25 PM
In this chapter, we will understand the Environment Variables, General Configuration, Database Configuration and Email Configuration in CakePHP.
PHP 8.4 Installation and Upgrade guide for Ubuntu and Debian
Dec 24, 2024 pm 04:42 PM
PHP 8.4 brings several new features, security improvements, and performance improvements with healthy amounts of feature deprecations and removals. This guide explains how to install PHP 8.4 or upgrade to PHP 8.4 on Ubuntu, Debian, or their derivati
CakePHP Date and Time
Sep 10, 2024 pm 05:27 PM
To work with date and time in cakephp4, we are going to make use of the available FrozenTime class.
CakePHP File upload
Sep 10, 2024 pm 05:27 PM
To work on file upload we are going to use the form helper. Here, is an example for file upload.
CakePHP Routing
Sep 10, 2024 pm 05:25 PM
In this chapter, we are going to learn the following topics related to routing ?
Discuss CakePHP
Sep 10, 2024 pm 05:28 PM
CakePHP is an open-source framework for PHP. It is intended to make developing, deploying and maintaining applications much easier. CakePHP is based on a MVC-like architecture that is both powerful and easy to grasp. Models, Views, and Controllers gu
CakePHP Creating Validators
Sep 10, 2024 pm 05:26 PM
Validator can be created by adding the following two lines in the controller.
How To Set Up Visual Studio Code (VS Code) for PHP Development
Dec 20, 2024 am 11:31 AM
Visual Studio Code, also known as VS Code, is a free source code editor — or integrated development environment (IDE) — available for all major operating systems. With a large collection of extensions for many programming languages, VS Code can be c
