Using JavaScript to develop a web voting system
Abstract:
With the rapid development of the Internet, online voting has become a convenient and fast way to collect public input and decision-making. This article will introduce the use of JavaScript to develop a simple web voting system, which enables users to select options and submit votes.
Introduction:
The web voting system is a program that displays multiple options on a web page and allows users to choose. It can be used in many scenarios, such as election voting, product surveys, opinion collection, etc. This article uses JavaScript to develop such a system and provides code examples.
Design idea:
- Create an HTML page that contains the display of options and voting buttons.
- Use JavaScript to write logic code to implement user selection and voting functions.
- Create a function for each option that responds to the click event and updates the voting results after the user selects it.
- Display voting results on the page.
Code example:
HTML part:
<!DOCTYPE html> <html> <head> <meta charset="UTF-8"> <title>网页投票系统</title> </head> <body> <h1 id="请选择你的喜爱选项">请选择你的喜爱选项</h1> <div id="options"> <div class="option"> <label><input type="radio" name="vote" value="option1">选项1</label> </div> <div class="option"> <label><input type="radio" name="vote" value="option2">选项2</label> </div> <div class="option"> <label><input type="radio" name="vote" value="option3">选项3</label> </div> <div class="option"> <label><input type="radio" name="vote" value="option4">选项4</label> </div> </div> <button onclick="vote()">投票</button> <h2 id="投票结果">投票结果:</h2> <div id="result"> <p>选项1: <span id="count1">0</span></p> <p>选项2: <span id="count2">0</span></p> <p>选项3: <span id="count3">0</span></p> <p>选项4: <span id="count4">0</span></p> </div> <script src="vote.js"></script> </body> </html>
JavaScript part (vote.js):
function vote() { var selectedOption = document.querySelector('input[name="vote"]:checked').value; var countElement = document.getElementById("count" + selectedOption); var count = parseInt(countElement.innerHTML); countElement.innerHTML = count + 1; }
Explanation:
## The- #HTML section creates a div containing the options and a radio input for each option.
- vote() function is an event triggered when the voting button is clicked. It first obtains the option value selected by the user and finds the corresponding count element.
- Then, convert the count value from a string to an integer via parseInt() and add 1 to the count value.
- Finally, the updated count value is displayed on the page.
Through the code examples provided in this article, we can develop a simple web voting system using JavaScript. Users can select options and submit votes, and the system will update the voting results in real time. Such a system can be used in various scenarios for convenient and efficient opinion collection and decision-making. With further extensions and improvements, we can also implement more complex voting functions.
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