[C#] BinaryWriter / BinaryReader

using(BinaryWriter bw = new BinaryWriter(new FileStream("test.dat", FileMode.Create)))
{
    bw.Write(12);
    bw.Write(3.14f);
    bw.Write("Hello World!");
}

int var1;
float var2;
string str1;

using (BinaryReader br = new BinaryReader(File.Open("test.dat", FileMode.Open)))
{
    var1 = br.ReadInt32();
    var2 = br.ReadSingle();
    str1 = br.ReadString();
}