Question

Why does char take 1 byte in Marshal.SizeOf while bool takes 4 bytes. Doesn’t char has more states than a bool

char c = '\x0011';
bool b = true;
Console.WriteLine("char: " + Marshal.SizeOf(c).ToString() + "\n" 
                + "bool: " + Marshal.SizeOf(b).ToString());

//char: 1
//bool: 4

Answer 1

You are looking at what the Marshal class makes of it. Try this to see what the compiler thinks:

 Console.WriteLine("char: " + sizeof(char).ToString() + "\n"
                 + "bool: " + sizeof(bool).ToString());

char : 2
bool : 1

Applying Marshal.SizeOf() to local variables isn’t the intended use. The basic idea is that you create a struct for interop and then the concept of padding becomes relevant.