Springmvc asynchronous File Upload and download

First look at how file is constructed:

1. File (String pathname): Gets the file object based on a path
2. File (String parent,string child): Gets the file object based on a directory and a sub-file/directory
3. File parent,string Child: Gets the file object based on a parent file object and a sub-file/directory

• Java.io.File.mkdir (): Only one level directory can be created and the parent directory must exist, otherwise a directory cannot be created successfully. Java.io.File.mkdirs (): You can create a multilevel directory, the parent directory does not necessarily exist

Implementing an asynchronous upload file requires no form labels. Front desk buy for:

Its corresponding Ajax is:

processdata:false//does not process data.

contenttype:false//do not set content type

In addition, due to the use of Ajax, you can not add its URL property in Formdata

The background code is implemented as:

Page effect:

Springmvc asynchronous File Upload and download