代码如下

<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <title>案例--表格全选</title>
    <style>
        table {
            border: 1px solid;
            margin: auto;
            width: 500px;
        }

        td, th {
            text-align: center;
            border: 1px solid;
        }

        .out {
            background-color: white;
        }

        .over {
            background-color: pink;
        }
        div{
            margin-top: 10px;
            text-align: center;
        }
    </style>
    <script>
        window.onload = function () {
            //全选
            document.getElementById("checkAll").onclick = function () {
                var cbs = document.getElementsByName("cb");
                for (var i = 0; i < cbs.length; i++) {
                    cbs[i].checked = true;
                }
            }
            //全不选
            document.getElementById("unCheckAll").onclick = function () {
                var cbs = document.getElementsByName("cb");
                for (var i = 0; i < cbs.length; i++) {
                    cbs[i].checked = false;
                }
            }
            //反选
            document.getElementById("reCheck").onclick = function () {
                var cbs = document.getElementsByName("cb");
                for (var i = 0; i < cbs.length; i++) {
                    cbs[i].checked = !cbs[i].checked;
                }
            }

            //鼠标经过，颜色变化
            var trs = document.getElementsByTagName("tr");
            for (var i = 0; i < trs.length; i++) {
                trs[i].onmouseover = function () {
                    this.className = "over";
                }
                trs[i].onmouseout = function () {
                    this.className = "out";
                }
            }

            //选中顶部复选框，全选
            document.getElementById("firstCb").onclick = function () {
                var cbs = document.getElementsByName("cb");
                for (var i = 0; i < cbs.length; i++) {
                    cbs[i].checked = this.checked;
                }
            }

        }

    </script>
</head>
<body>
<table>
    <caption>学生信息表</caption>
    <tr>
        <td><input type="checkbox" name="cb" id="firstCb"></td>
        <td>编号</td>
        <td>姓名</td>
        <td>性别</td>
        <td>操作</td>
    </tr>
    <tr>
        <td><input type="checkbox" name="cb"></td>
        <td>1</td>
        <td>令狐冲</td>
        <td>男</td>
        <td><a href="javascript:void(0);" onclick="delTr(this)">删除</a></td>
    </tr>

    <tr>
        <td><input type="checkbox" name="cb"></td>
        <td>2</td>
        <td>任我行</td>
        <td>男</td>
        <td><a href="javascript:void(0);" onclick="delTr(this)">删除</a></td>
    </tr>

    <tr>
        <td><input type="checkbox" name="cb"></td>
        <td>3</td>
        <td>岳不群</td>
        <td>?</td>
        <td><a href="javascript:void(0);" onclick="delTr(this)">删除</a></td>
    </tr>
</table>
<div>
    <input type="button" value="全选" id="checkAll">
    <input type="button" value="全不选" id="unCheckAll">
    <input type="button" value="反选" id="reCheck">
</div>


</body>
</html>