使用文件类型输入时检索文件名

Question

我有一个jsp带有此代码段的代码片段.

<form name="AudioFileConversionForm" enctype="multipart/form-data" method="post" >
Choose File: <input type="file" id="audioFile" name="audioFile"><br>
<input type="submit" value="upload">
</form>

这是我的控制器spring.

public String convertFile(HttpServletRequest request, HttpSession session) {

    String audioFile = request.getParameter("audioFile");
    System.out.println(request.getParameter("audioFile"));
    System.out.println("Audio File Conversion Successful");
}

它显示我无法检索文件的名称null.我知道我可以使用JQuery或javascript检索名称,但我不想同时使用它们.我想用纯java来做.谁能帮帮我吗？

Answer 1

上传文件时,request是实例org.springframework.web.multipart.MultipartHttpServletRequest.所以你可以把它投射到你的方法中convertFile().见下文 :

public String convertFile(HttpServletRequest request, HttpSession session) {
    // cast request
    MultipartHttpServletRequest multipartRequest = (MultipartHttpServletRequest) request;
    // You can get your file from request
    CommonsMultipartFile multipartFile =  null; // multipart file class depends on which class you use assuming you are using org.springframework.web.multipart.commons.CommonsMultipartFile

    Iterator<String> iterator = multipartRequest.getFileNames();

    while (iterator.hasNext()) {
        String key = (String) iterator.next();
        // create multipartFile array if you upload multiple files
        multipartFile = (CommonsMultipartFile) multipartRequest.getFile(key);
    }

    // logic for conversion
}

但是我无法检索(接收空值)我在JSP页面中选择的文件的名称.

--->要获取文件名,您可以将其作为:

multipartFile.getOriginalFilename();  // get filename on client's machine
multipartFile.getContentType();       // get content type, you can recognize which kind of file is, pdf or image or doc etc
multipartFile.getSize()          // get file size in bytes

要使文件上传起作用,您需要确保创建多部分解析器bean,如下所示:

<bean id="multipartResolver"
    class="org.springframework.web.multipart.commons.CommonsMultipartResolver">

    <!-- one of the properties available; the maximum file size in bytes -->
    <property name="maxUploadSize" value="100000"/>
</bean>

参考:Spring文档