怎么将一段字符转换成MultipartFile

Posted 2023-04-18

参考技术A 使用Java中的File类，url为文件的绝对地址，str为输入的字符串内容。代码如下图所示：Stringstr="ilovechina!"Filetxt=newFile("url");if(!txt.exists())txt.createNewFile();bytebytes[]=newbyte[512];bytes=str.getBytes();//新加的intb=str.length();//改FileOutputStreamfos=newFileOutputStream(txt);fos.write(bytes,0,b);fos.close();

File转换成MultiPartFile

1.首先获取FileItem对象：
public FileItem createFileItem(String filePath) 
    FileItemFactory factory = new DiskFileItemFactory(16, null);
    String textFieldName = "textField";
    int num = filePath.lastIndexOf(".");
    String extFile = filePath.substring(num);
    FileItem item = factory.createItem(textFieldName, "text/plain", true, "MyFileName");
    File newfile = new File(filePath);
    int bytesRead = 0;
    byte[] buffer = new byte[8192];
    try 
        FileInputStream fis = new FileInputStream(newfile);
        OutputStream os = item.getOutputStream();
        while ((bytesRead = fis.read(buffer, 0, 8192)) != -1) 
            os.write(buffer, 0, bytesRead);
        
        os.close();
        fis.close();
     catch (IOException e) 
        e.printStackTrace();
    
    return item;





2.通过FileItem对象可以轻松获得CommonsMultipartFile对象，转换成MultiPartFile对象即可使用。

MultipartFile mfile = new CommonsMultipartFile(fileItem);

参考： https://segmentfault.com/a/1190000015706485