io¶

if you use StreamWriter and StreamReader without the FileStream, FileStream will be automatically created. But when you created FileStream by yourself, you have options to specify file mode and share access.

system shutdown¶

StreamWriter Writing NUL characters at the end of the file when system shutdown abruptly

write to file¶

const int BufferSize = 65536;  // 64 kB
var writer = new StreamWriter("filename", true, Encoding.UTF8, BufferSize);

using (var writer = new StreamWriter(filepath, true, Encoding.UTF8, 65536)) {
    for (int i = 1; i < repeats; i++) {
        writer.WriteLine("Some line of text");
    }
}

write to zipped csv file¶

using(var zf = ZipFile.Open("file.zip", ZipArchiveMode.Create)) {
   var ze = zf.CreateEntry("file.csv");
   using(var zs = ze.Open()) {
      using(var sw = new StreamWriter(zs, Encoding.UTF8)) {
         sw.WriteLine("Name,Address,Email")
      }
   }
}

concurrent write and read file¶

var writer = File.Open("C:\\f.txt", FileMode.Create, FileAccess.Write, FileShare.ReadWrite));
var reader = new StreamReader(File.Open("C:\\f.txt", 
                                      FileMode.Open, FileAccess.Read, FileShare.ReadWrite)));

append to log file¶

public static void ToFile(string msg, bool writeline = false)
{
    using (var w = File.AppendText(_logpath)) {
        if (!writeline) {
            w.Write(msg);
        }
        else {
            w.WriteLine(msg);
        }
    }
}

color console¶

public static void ConsoleColorWLine(string msg, ConsoleColor? fgc = null, ConsoleColor? bgc = null)
{
    ConsoleColorWrite($"{msg}\n", fgc, bgc);
}

public static void ConsoleColorWrite(string msg, ConsoleColor? fgc = null, ConsoleColor? bgc = null)
{
    var fgColor = Console.ForegroundColor;
    if (fgc.HasValue) {
        Console.ForegroundColor = fgc.Value;
    }
    var bgColor = Console.BackgroundColor;
    if (bgc.HasValue) {
        Console.BackgroundColor = bgc.Value;
    }
    Console.Write(msg);
    if (fgc.HasValue) {
        Console.ForegroundColor = fgColor;
    }
    if (bgc.HasValue) {
        Console.BackgroundColor = bgColor;
    }
}