why can't I assign 1.2 value to float variable in C#? I did the same in C and C++, and it worked

Question

why can't I assign 1.2 value to float variable in C#? I did the same in C and C++, and it worked.

class Program
{
    private readonly int a = 20;
    private readonly float b;      

    public Program(float tmp)
    {
        b = tmp;
    }
    static void Main(string[] args)
    {
        Program obj1 = new Program(1.2);
        Console.Read();
    }
}

It gives error can not convet double to float. Why is so isn't 1.2 float value?

Answer 1

1.2 is a double (8 bytes).
1.2f is a float (4 bytes).

More details

Answer 2

Any literal number in your code which includes a decimal point is interpreted as a double, not a float, unless you mark it as a float by appending f.

Doubles are not automatically converted to floats, since this can result in a loss of precision.

To fix your code, you can either:

• mark your literal number as a float:

  Program obj1 = new Program(1.2f);

• or, explicitly cast it as a float:

  Program obj1 = new Program((float)1.2);

The former option should be preferred when using a numeric literal, but if you are passing a variable typed as a double, then you can use the latter one.