Append lines to a file using a StreamWriter

c# streamwriter
Waypoint picture Waypoint · Sep 5, 2011 · Viewed 386.2k times · Source

I want to append lines to my file. I am using a StreamWriter:

StreamWriter file2 = new StreamWriter(@"c:\file.txt");
file2.WriteLine(someString);
file2.Close();

The output of my file should be several strings below each other, but I have only one row, which is overwritten every time I run this code.

Is there some way to let the StreamWriter append to an existing file?

Answer

Øyvind Bråthen picture Øyvind Bråthen · Sep 5, 2011

Use this instead:

new StreamWriter("c:\\file.txt", true);

With this overload of the StreamWriter constructor you choose if you append the file, or overwrite it.

C# 4 and above offers the following syntax, which some find more readable:

new StreamWriter("c:\\file.txt", append: true);

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