Tutorial by Examples

HTML Form Use a file type input and the browser will provide a field that lets the user select a file to upload. Only forms with the post method can send file data. Make sure to set the form's enctype=multipart/form-data attribute. Otherwise the file's name will be sent but not the file's data...

Uploaded files are available in request.files, a MultiDict mapping field names to file objects. Use getlist — instead of [] or get — if multiple files were uploaded with the same field name. request.files['profile'] # single file (even if multiple were sent) request.files.getlist('charts') # li...

WTForms provides a FileField to render a file type input. It doesn't do anything special with the uploaded data. However, since Flask splits the form data (request.form) and the file data (request.files), you need to make sure to pass the correct data when creating the form. You can use a Combine...

Developers often need to design web sites that allow users to upload a CSV file. Usually there is no reason to save the actual CSV file since the data will processed and/or stored in a database once uploaded. However, many if not most, PYTHON methods of parsing CSV data requires the data to be rea...