The Solutions already given with a suggestion to use
\"
are good.
As an alternative if you want to use
verbatim string literal
explained here
http://msdn.microsoft.com/en-us/library/aa691090(v=vs.71).aspx[
^] then
""
can be used to include
"
within a string as shown below:
string text = @"<<MAWB>>,""160-3636 4834"",2012/06/12,""CX500"",2012/06/03,17,0";
System.IO.File.WriteAllText(outFile,text);