Tkinter, asksaveasfile, and unicode

I checked the code for asksaveasfile and indeed it only passes the filename and mode to open. It is strictly a convenience function combining a call to asksaveasfilename with a call to open(filename, mode), with all other args defaulted. So don't use it.

Instead, use asksaveasfilename and explicitly open the file yourself, just as you did for for the source file. You can then write the open call you want, with encoding='utf-8' and any other non-default options.

The first with should end after you have read Usefile and have no further need of it. The if statement should therefore be dedented.

Assuming that you are using Python 3 (tkinter.filedialog strongly suggests that you are), the file will be opened with the locale encoding as returned by locale.getpreferredencoding(). If that is already UTF-8 then you should be able to write directly to the file without explicitly encoding the strings.

However, because you are encrypting the file, crypt() probably returns a bytes string, not a str (unicode) string. If this is the case then you should open the input and output files in binary mode. Then no encoding is required when writing to the output file.

name = fudder.askopenfilename(defaultextension =("Python Files","*.py"),title = "Choose a file to encrypt.")with open(name, 'rb') as Usefile:    filecont = Usefile.read()    if filecont is None:        return    else:        result = crypt(filecont)        if result is None:            return        with fudder.asksaveasfile(mode = 'wb', defaultextension = '.txt', title = 'Save the decrypted file.') as newf:            newf.write(result[0])            newf.write(b'\n\n\nKey:\n\n\n')            newf.write(result[1])

The key differences are:

• Files are opened in binary mode
• No encoding
• Save dialog is not displayed if crypt() returns None