FORM的ENCTYPE="multipart/form-data" request.getParameter()获取不到值

Situation:

javax.servlet.HttpServletRequest.getParameter(String) returns null when the ContentType is multipart/form-data

Solutions:

1. Download one of the versions of UploadFile from http://jakarta.apache.org/commons/fileupload/ 2. Invoke parseRequest(request) on org.apache.commons.fileupload.FileUploadBase which returns list of org.apache.commons.fileupload.FileItem objects.
3. Invoke isFormField() on each of the FileItem objects. This determines whether the file item is a form paramater or stream of uploaded file.
4. Invoke getFieldName() to get parameter name and getString() to get parameter value on FileItem if it's a form parameter. Invoke write(java.io.File) on FileItem to save the uploaded file stream to a file if the FileItem is not a form parameter.

这篇文章给出了一个demo，可以参考 http://blog.csdn.net/liuyuhua0066/article/details/8782716