Question

我试图从嵌入在我的jsp文件中的文本编辑器传递格式化文本。我在表单标签中使用了enctype =“multipart / form-data”。我可以在使用默认的enctype时将参数传递给underyling servlet。但是在我的servlet中使用multipart / form-data enctype时我得到null。

我的表格

<form action="pdfGenServlet" method="post" enctype="multipart/form-data">
                    <!-- input notes title-->
                    <div class="form-group">
                        <div class="input-group">
                            <input type="text" class="form-control" placeholder="Title of the notes" name="title">
                        </div>
                    </div>
                    <!-- input notes description-->
                    <div class="form-group">
                        <div class="input-group">
                            <input type="text" class="form-control" placeholder="Enter short description" name="description">
                        </div>
                    </div>

                    <div class="form-group">
                      <textarea name="content" id="myEditor"></textarea>

                     <div id="button-panel" class="panel panel-default">
                          <p>
                              <button type="submit" class="btn btn-primary "><span class="glyphicon glyphicon-plus"></span><strong> Create Note</strong></button>
                              <button class="btn btn-primary" type="reset"><strong>Reset</strong></button>
                          </p><!-- buttons -->
                     </div><!-- panel Button -->

                    </div>

                </form>

我的pdfGenServlet.java

  @WebServlet("/pdfGenServlet")
 public class pdfGenServlet extends HttpServlet {
private static final long serialVersionUID = 1L;

/**
 * @see HttpServlet#doPost(HttpServletRequest request, HttpServletResponse response)
 */
protected void doPost(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
      try {
            // Get the text that will be added to the PDF
            request.setCharacterEncoding("UTF-8");

            String title = request.getParameter("title");
            String description = request.getParameter("description");
            String notes_content = request.getParameter("content");
            Date date = new Date();
        } catch(exception e)
        {e.printStackTrace();}
      }

Answer 1

我通过使用以下代码解决了这个问题。您应该在Servlet类中添加@MultipartConfig批注：例如：

@WebServlet("/admin/create_book")
@MultipartConfig(
        fileSizeThreshold = 1024 * 10,  // 10 KB
        maxFileSize = 1024 * 300,       // 300 KB
        maxRequestSize = 1024 * 1024    // 1 MB 
)
public class CreateBookServlet extends HttpServlet {
    private static final long serialVersionUID = 1L;
       
    public CreateBookServlet() {
        super();
    }

    
    protected void doPost(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
        BookServices bookServices = new BookServices(request, response);
        bookServices.createBook();
    }

}

Answer 2

请参阅以下链接，它将帮助您上传带有输入参数的图像：

http://www.avajava.com/tutorials/lessons/how-do-i-upload-a-file-to-a-servlet.html

Answer 3

如果要从HTML（JSP）表单获取该内容属性为“ enctype =“ multipart / form-data”“的参数。

您应该在将接收所有这些参数的servlet中添加@MultipartConfig（也应在Convey / Dispatch Servlet中添加@MutipartConfig）。
@MultipartConfig中包含三个元素：fileSizeThreshold，maxFileSize，maxRequestSize;
（我使用Servlet 3 File Upload上传文件）

在表单中使用multipart / form-data enctype时，无法将参数传递给servlet

3 个答案: