File reading basics

Great. We have written a file. Now we should be able to read it as well, right? Okay, let’s dive into that. We will start with a simple example: a file with some lines of text that we want to read into a string:

public string ReadFromFile(string fileName)
{
    var text = File.ReadAllText(fileName);
    return text;
}

I can’t make it simpler than this. We have the static ReadAllText method, which takes a filename and reads all text into the string. Then we return that. Keep in mind that not all files contain text. I even dare to say that most files do not contain text. They are binary. Now, technically, a text file is also a binary file. So, let’s read the file again, but now by reading the actual bytes. I use the FileStream this time, so we have a bit more control over what is happening:

public string ReadWithStream(string fileName)
{
    byte[] fileContent;
   ...