Capture standard output of another command-line program, with characters not in current codepage

Question

I'm using ProcessStartInfo.RedirectStandardOutput and Process.BeginOutputReadLine to capture the standard output of another program (specifically,
youtube-dl.exe) and save them into a string variable.
However the result variable contains only usual characters of my language such as traditional Chinese and English letters; characters such as Korean or Latin letters with accents simply vanished.
I File.WriteAllText-ed the result variable and checked the file using serveral text editors, so I'm sure they're lost, not that they exist and merely be un-display-able by console window.
Plainly executing youtube-dl in Windows Command Prompt displays complete messages including these foreign characters.  
My youtubeDL_process.OutputDataReceived is simply:
(s, e) => { if(!string.IsNullOrWhiteSpace(e.Data)) this._filename = e.Data; }
How to make the redirected standard output string with foreign characters complete, just like one directly generated in a command prompt?

Answer 1

Try a different experiment of starting your second EXE:
string exe =
@"path to your EXE with arguments . . .";
Process p =
new
Process
StartInfo =
UseShellExecute = false,
RedirectStandardOutput = true,
StandardOutputEncoding = Encoding.UTF8,
FileName = "cmd.exe",
Arguments = "/C chcp 65001 > null && " + exe
p.Start();
string output = p.StandardOutput.ReadToEnd();
p.WaitForExit();
Specify the full path in the exe variable, using quotation marks if it contains spaces.
Then check the value of output.