How to truncate a file in c#?

Question

I am writing actions done by the program in C# into a file by using Trace.Writeln() function. But the file is becoming too large. How to truncate this file when it grows to 1MB?

TextWriterTraceListener traceListener = new TextWriterTraceListener(File.AppendText("audit.txt"));
Trace.Listeners.Add(traceListener);
Trace.AutoFlush = true;

What should be added to the above block

Answer 1

Try to play around with FileStream.SetLength

FileStream fileStream = new FileStream(...);
fileStream.SetLength(sizeInBytesNotChars);

Answer 2

Close the file and then reopen it using FileMode.Truncate.

Some log implementations archive the old file under an old name before reopening it, to preserve a larger set of data without any file getting too big.