Question

我有一个调用MySQL数据库的servlet。

deletePage方法如下所示：

public void  deletePage(PageData delete) {
    String firstQuery ="Delete FROM pages Where ID= '"+delete.getId()+"';";

    try {
        statement = connection.createStatement();
        statement.executeUpdate(firstQuery);
        System.out.println("Expense is deleting");

    } catch (SQLException e) {
        System.out.println("Expense isn't deleting - SQLException");
        e.printStackTrace();
    }
}

delete.jsp如下：

<html>
    <head>
        <meta http-equiv="Content-Type" content="text/html; charset=UTF-8">
        <title>Add pages</title>
    </head>
    <body>
        <form action="adminController">
            <p>
                <input type="hidden" name="operation" value="deletepage" />
                <input type="hidden" name="parentid" value="<%= request.getParameter("id") %>" />
                Enter ID of page you want to delete:<input name="id"><br>

                <input type="submit" />
            </p>
        </form>
    </body>
</html>

mainadmin.jsp：

<html>
    <head>
        <meta http-equiv="Content-Type" content="text/html; charset=UTF-8">
        <title>Insert title here</title>
    </head>
    <body>
        <%= request.getAttribute("menu") %>
    </body>
</html>

如果您运行此代码，您会看到我的删除按钮位于每个页面名称之后。我想要做的是按下页面附近的删除按钮删除此页面，应该有“你确定要删除吗？”，提交按钮“删除”。但我设法做的就像这样（在我的代码中）：每当按下删除按钮，你必须输入你要删除的页面的id，所以无论我按什么删除按钮，它都会请求id。但我只想立即删除它。有人可以帮忙吗？

Answer 1

你在adminController.java中的

else if (operation.equals("delete")) {
    RequestDispatcher dispatcher = request.getRequestDispatcher("/delete.jsp");
    dispatcher.forward(request, response);

} else if (operation.equals("deletepage")) {
    PageData pageData = new PageData();
    pageData.setId(request.getParameter("id"));
    dao.deletePage(pageData);
    response.sendRedirect("adminController");
}

将其更改为

else if (operation.equals("delete")) {
    PageData pageData = new PageData();
    pageData.setId(request.getParameter("id"));
    dao.deletePage(pageData);
    response.sendRedirect("adminController");
}

您不需要第二个操作'deletepage'，因此您不需要delete.jsp

通过servlet / jsp从mysql数据库中删除数据

1 个答案: