The result of request.getParameter is on

The reason is that there is no settingvalue

例如：

性别：
        <label for="man">男</label>
        <input type="radio" name="sex" id="man" checked>
        <label for="woman">女</label>
        <input type="radio" name="sex" id="woman" ><br><br>

性别：
        <label for="man">男</label>
        <input type="radio" name="sex" id="man" value="男" checked>
        <label for="woman">女</label>
        <input type="radio" name="sex" id="woman" value="女" ><br><br>

The difference is thatvalue="男"和value=“女”
设置value后,The data can be obtained normally