使用enctype =“ multipart / form-data”将选定的图像获取到控制器类吗？

Question

JSP：

<form action="addUpdateSchool" method="post" enctype="multipart/form-data">
        <table align="center">
            <tr>
                <td>School Name :</td>
                <td><input type="text" id="school_name" name="school_name" /></td>
            </tr>
            <tr>
                <td>Address :</td>
                <td><textarea rows="4" cols="30" id="address" name="address"></textarea> </td>
            </tr>
             <tr>
                <td>Logo :</td>
                <td><input type="file" id="logo" name="logo"/></td>
            </tr>
             <tr>
                <td><input type="submit" onclick="return validation();" /></td>
            </tr>
        </table>
    </form>

我正在尝试在Controller类中获取所有上述表单属性，包括徽标，但其显示为null。

我该如何解决？

控制器类别：

@RequestMapping(value = "/addSchool", method = RequestMethod.POST)
    public String addSchool(@ModelAttribute SchoolModel schoolModel, HttpSession session) {

     System.out.println("name: "+schoolModel.getSchool_name);

} 

Answer 1

您必须在应用程序上下文中添加multipartResolver才能在视图页面中处理enctype="multipart/form-data" 。 在您的应用程序contex xml文件中添加以下内容

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

并在您的类路径中添加适当的jar文件。

有关更多信息，请参见此处的春季文档。

Answer 2

dispatcher-servlet.xml

<bean id="multipartResolver" class="org.springframework.web.multipart.commons.CommonsMultipartResolver">
    <property name="maxUploadSize" value="10000000" /> <!-- setting maximum upload size -->
</bean>

控制器类别：

@RequestMapping(value = "/addUpdateSchool", method = RequestMethod.POST)
public String addSchool(@RequestParam("logo") MultipartFile multipartFile, @ModelAttribute SchoolModel schoolModel) {
    String path="";
    try{
        MultipartFile file = multipartFile;
        if(file.getOriginalFilename().trim().length()>0) {
            path=saveFile(file, multipartFile.getOriginalFilename());
        }else{
            path="";
        }
        System.out.println("path: "+path);
    }catch(Exception e){
        e.printStackTrace();
    }
}

public static String saveFile(MultipartFile file, String name) throws IOException{
    byte[] bytes = file.getBytes();
    Random random = new Random();       
    File dir = new File("D:\WebSLCMImages\WebSLCM\"); // Path to Save Image
    if (!dir.exists()){
        dir.mkdirs();
    }
    String path = dir+"/" + getFileName(name) + System.currentTimeMillis() + Math.abs(random.nextInt())+ getFileExtension(name);
    File serverFile = new File(path);
    BufferedOutputStream stream = new BufferedOutputStream(new FileOutputStream(serverFile));
    stream.write(bytes);
    stream.close();
    return path;
}

注意：不要忘记添加相关的jar文件（commons-fileupload-1.3.jar）

参考链接： MVC-Multipart-Resolver