Menu
Append to a Text File With the File. AppendAllText() Method in C# The File. AppendAllText() method in C# is used to open an existing file, append all the text to the end of the file and then close the file.
To append to a text fileUse the WriteAllText method, specifying the target file and string to be appended and setting the append parameter to True . This example writes the string "This is a test string." to the file named Testfile. txt .
StreamWriter. Write() method is responsible for writing text to a stream. StreamWriter class is inherited from TextWriter class that provides methods to write an object to a string, write strings to a file, or to serialize XML. StreamWriter is defined in the System.IO namespace.
The first step to creating a new text file is the instantiation of a StreamWriter object. The most basic constructor for StreamWriter accepts a single parameter containing the path of the file to work with. If the file does not exist, it will be created. If it does exist, the old file will be overwritten.
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);
using (FileStream fs = new FileStream(fileName,FileMode.Append, FileAccess.Write))
using (StreamWriter sw = new StreamWriter(fs))
{
sw.WriteLine(something);
}
I assume you are executing all of the above code each time you write something to the file. Each time the stream for the file is opened, its seek pointer is positioned at the beginning so all writes end up overwriting what was there before.
You can solve the problem in two ways: either with the convenient
file2 = new StreamWriter("c:/file.txt", true);
or by explicitly repositioning the stream pointer yourself:
file2 = new StreamWriter("c:/file.txt");
file2.BaseStream.Seek(0, SeekOrigin.End);
Try this:
StreamWriter file2 = new StreamWriter(@"c:\file.txt", true);
file2.WriteLine(someString);
file2.Close();
Replace this:
StreamWriter file2 = new StreamWriter("c:/file.txt");
with this:
StreamWriter file2 = new StreamWriter("c:/file.txt", true);
true indicates that it appends text.
Use this StreamWriter constructor with 2nd parameter - true.
If you love us? You can donate to us via Paypal or buy me a coffee so we can maintain and grow! Thank you!
Donate Us With