今天在原來上傳文件頁面的基礎上，想添加一段文件的簡介

因為同時要上傳文件，所以ENCTYPE="multipart/form-data" 必須要加在form里面

可是這樣的話，我再servlet里面用request.getParameter()方法無論如何都只是獲得null值，

不是一般的郁悶，百度了一下，有人出現了同樣的問題可是它用的是jspsmartupload組件實現文件上傳的，

而我用的commons fileupload組件，仔細看了一下這個組件的api，可是英語太差了，沒有發現相關的信息

我又嘗試用session傳遞參數，可是發現有點麻煩，因為在表單提交之時你就得賦給session表單上它的數值，

這似乎要javascript，可是偶也不會，

后來只有google了，搜索了一些中文網頁，也沒有找到資料，試試不限制語言，呵呵呵，一大片，后來被俺發

現了這個

I cannot read the submitter using request.getParameter("submitter") (it returns null). ]

Situation:

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

Solutions:

Solution A:

1. download http://www.servlets.com/cos/index.html
2. invoke getParameters() on com.oreilly.servlet.MultipartRequest

Solution B:

1. download http://jakarta.apache.org/commons/sandbox/fileupload/
2. invoke readHeaders() in 
org.apache.commons.fileupload.MultipartStream

Solution C:

1. download http://users.boone.net/wbrameld/multipartformdata/
2. invoke getParameter on 
com.bigfoot.bugar.servlet.http.MultipartFormData

Solution D:

Use Struts. Struts 1.1 handles this automatically.

說是不詳細，接著往下看，另一種解決方法

> Solution B:
> 1. download 
> http://jakarta.apache.org/commons/sandbox/fileupload/
> 2. invoke readHeaders() in 
> org.apache.commons.fileupload.MultipartStream

The Solution B as given by my dear friend is a bit hectic and a bit complex :(
We can try the following solution which I found much simpler (at least in usage).

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. 

按照上面的步驟來，果然一切都ok，ＧＯＯＧＬＥ真不錯，主要是getFieldName和getString，

雖然說這種做法有一點麻煩，但稍微判斷加工一下，總比獲取不到強