Java如何将MultipartFile转为File

MultipartFile multiFile = new MultipartFile(); //前端传过来的文件对象

String fileName = ();
String prefix = (("."));

File file = null;
try {

     file = (fileName, prefix);
     (file);
} catch (Exception e) {
     ();
            
} finally {
     // 操作完上面的文件 需要删除在根目录下生成的临时文件
     File f = new File(());
     ();
}

以上方法如果涉及跨域很有可能不能使用，建议使用以下方法

 //调用
 File file = null;
 try {
      //将MultipartFile转为File
      file = multipartFileToFile(multiFile);
     } catch (Exception e) {
          ();
          ("上传失败，请检查文件格式再次尝试");
          (false);
          return result;
     } finally {
          deleteTempFile(file);
     }

//工具类
import ;

import ;
import ;
import ;
import ;

/**
 * @Auther: QiShuai
 * @Date: 2020/4/8 10:58
 * @Description:
 */
public class MultipartFileToFile {
    /**
     * MultipartFile 转 File
     *
     * @param file
     * @throws Exception
     */
    public static File multipartFileToFile(MultipartFile file) throws Exception {

        File toFile = null;
        if (("") || () <= 0) {
            file = null;
        } else {
            InputStream ins = null;
            ins = ();
            toFile = new File(());
            inputStreamToFile(ins, toFile);
            ();
        }
        return toFile;
    }

    //获取流文件
    private static void inputStreamToFile(InputStream ins, File file) {
        try {
            OutputStream os = new FileOutputStream(file);
            int bytesRead = 0;
            byte[] buffer = new byte[8192];
            while ((bytesRead = (buffer, 0, 8192)) != -1) {
                (buffer, 0, bytesRead);
            }
            ();
            ();
        } catch (Exception e) {
            ();
        }
    }

    /**
     * 删除本地临时文件
     * @param file
     */
    public static void deleteTempFile(File file) {
        if (file != null) {
            File del = new File(());
            ();
        }
    }
}