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我需要通过 AJAX 调用从 extjs 页面将文件上传到服务器。我可以使用简单的 HTML 页面到 servlet 来做到这一点，但是使用 extjs（v4.0.7）我在解析请求时没有在我的 servlet 中获取文件。Servlet 识别多部分页面，但调用没有任何内容。谁能告诉我我在代码中做错了什么？

EXTJS代码：

var fileName = Ext.getCmp("fileName").getValue();

Ext.Ajax.request({
    url : 'UploadServlet',
    method: 'POST',  
    headers: {'Content-Type': 'multipart/form-data'},
    params :{
       'fileName': fileName.trim()
    },

    success: function ( result, request ) {
        resultData = result.responseText;
    },
    failure: function ( result, request ) {
        resultData = result.responseText;
    }   
});

小服务程序代码：

protected void doPost(HttpServletRequest request,HttpServletResponse response)
        throws ServletException, IOException {  

    .......

     // Check that we have a file upload request
      isMultipart = ServletFileUpload.isMultipartContent(request);
      response.setContentType("text/html");
      java.io.PrintWriter out = response.getWriter( );
      if( !isMultipart ){
          // display no file attached error
         return;
      }

      // Create a factory for disk-based file items
      DiskFileItemFactory factory = new DiskFileItemFactory();
      // maximum size that will be stored in memory
      factory.setSizeThreshold(maxMemSize);
      // Location to save data that is larger than maxMemSize.
      factory.setRepository(new File(tempDir));

      // Create a new file upload handler
      ServletFileUpload upload = new ServletFileUpload(factory);
      // maximum file size to be uploaded.
      upload.setSizeMax( maxFileSize );


      try{ 
          // Parse the request to get file items.

      ////// fileItems is empty, 
              ////nothing is comming from extjs page/////////
          List<FileItem> fileItems = upload.parseRequest(request);

          // Process the uploaded file items
          Iterator<FileItem> i = fileItems.iterator();

          while ( i.hasNext () ) {                
             FileItem fi = (FileItem)i.next();

             if ( !fi.isFormField () ) {
                // Get the uploaded file parameters
                String fieldName = fi.getFieldName();
                String fileName = fi.getName();
                String contentType = fi.getContentType();
                boolean isInMemory = fi.isInMemory();
                long sizeInBytes = fi.getSize();

                // check if file exists
                File propFile = new File(tempDir, fileName.substring( fileName.lastIndexOf("\\")));
                if (!propFile.exists()) {  
                    // Write the file
                    if( fileName.lastIndexOf("\\") >= 0 ){
                       file = new File(tempDir + 
                       fileName.substring( fileName.lastIndexOf("\\"))) ;
                    }else{
                       file = new File(  tempDir + 
                       fileName.substring(fileName.lastIndexOf("\\")+1)) ;
                    }   
                    //InputStream uploadedStream = fi.getInputStream();
                    fi.write( file ) ;
                    out.println("Uploaded Filename: " + fileName + "  is in " + filePath + "<br>");
                } 

                ..... 
             }
          }
4

1 回答 1

6

You can't upload a file with AJAX.

Ext's Ajax can emulate it though. See the doc of the request method. You have to use the form and isUpload options.

However, since you have to use a form anyway, you should look at Ext.form.field.Field (and, as suggested in the doc, to Ext.form.Basic.hasUpload; that will give you a better understanding of the file upload problematic).

EDIT: In fact, HTML5 and XMLHttpRequest Level 2 adds support for file upload. Doesn't change how you have to handle it in Ext, though.

于 2013-06-11T23:52:25.460 回答