简易图书管理系统

一、HTML代码

<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <title>图书管理系统</title>
</head>
<body background="bg.jpg" style="background-repeat: no-repeat;background-size: cover;">
    <h1 style="text-align: center;">图书管理系统</h1>
    <p style="text-align: center">
        <span>书名</span><input type="text" id="bookName">
        <span>作者</span><input type="text" id="bookAuthor">
        <span>价格</span><input type="text" id="bookPrice">
        <span>数量</span><input type="text" id="bookCount">
    </p>
    <p style="text-align: center">
        <button id="add">添加</button>
        <button id="query">查询</button>
    </p>
    <hr/>
    <div id="showMessage"></div>
</body>
</html>
 

二、JavaScript代码

<script>
        //1.获取页面的元素
        var bookNameInput = document.getElementById('bookName');
        var bookAuthorInput = document.getElementById('bookAuthor');
        var bookPriceInput = document.getElementById('bookPrice');
        var bookCountInput = document.getElementById('bookCount');
        var addBtn = document.getElementById('add');
        var queryBtn = document.getElementById('query');
        var showDiv = document.getElementById('showMessage');
        //1.1.准备二维数组用来承载数据
        var bookArr = [];
        //2.给Button添加点击事件
        //2.1添加按钮
        addBtn.onclick = function () {
           //2.10获取页面的内容
            var bookName = bookNameInput.value;
            var bookAuthor = bookAuthorInput.value;
            var bookPrice = bookPriceInput.value;
            var bookCount = bookCountInput.value;
            //2.11对页面的内容进行判断
            //2.12元素内容不完整
            if (bookName.trim().length == 0 || bookAuthor.trim().length == 0 || bookPrice.trim().length == 0
                || bookCount.trim().length == 0){
                alert('您输入的数据不完整,请重新输入');
            }else {
                //2.13元素内容完整
                //2.14向数组中添加元素
                var arr = [];
                arr.push(bookName);
                arr.push(bookAuthor);
                arr.push(bookPrice);
                arr.push(bookCount);
                bookArr.push(arr);
                console.log(bookArr);
                //2.15清除历史记录
                bookNameInput.value = '';
                bookAuthorInput.value = '';
                bookPriceInput.value = '';
                bookCountInput.value = '';
            }
        };
        //2.2展示按钮
        queryBtn.onclick = function () {
            //判断二维数组是否有元素
            //2.21二维数组没有元素
            if (bookArr.length == 0){
                alert('没有数据,请添加');
            }else {
                //2.22二维数组有元素
                //构建表格,并添加相应的元素
                var str = '<table border="1" cellspacing=0  width="600px" align="center" style="text-align: center;">'+
                        '<tr> <td>书名</td>  <td>作者</td> <td>价格</td> <td>数量</td> </tr>'
                //注意表格的行数是动态增加的
                for (var i = 0; i < bookArr.length;i++){
                        str += '<tr><td>'+ bookArr[i][0] +'</td>'+
                                          '<td>'+bookArr[i][1]+'</td>' +
                                          '<td>'+bookArr[i][2]+'</td>' +
                                          '<td>'+bookArr[i][3] +'</td> </tr>';
                }
                str += '</table>';
                //展示表格
                showDiv.innerHTML = str;
            }
        };
    </script>

主要功能:通过填写书名、作者、价格和数量,再点击添加,然后点击查询按钮,将会把查询结果显示出来。

运行结果示例:

 

原文地址:https://www.cnblogs.com/my-program-life/p/11603397.html