C＃：隐式将double转换为float？

Question

I know implicit conversions from double to float are not allowed by default in C#, but is there any way I can enable such conversions? With a pragma of some sort? I'm not concerned with lack of precision (as my application doesn't require more than float precision anywhere), moreso just annoyed with having to always ensure I explicitly declare all decimal values as floats, or else I get compilation errors.

Answer 1

No you can't. Since such a conversion could result in a precision loss, and the compiler has no way of determining whether it will or will not, you have to explicitly say that you're aware of the cast.

I'm unsure of what you mean by "explicitly declare decimals as floats", but in case you did not now, you can tell that a literal is a float by adding an f at the end

float a = 0.0;  // Wrong, implicit conversion.
float b = 0.0f; // OK. Can also be capital 'F'.

But if you're complaining about adding this one letter everywhere as a burden, then sorry, the answer is no, you can't work around that.

Answer 2

No, there isn't any way to do it with implict conversion, but you may do it that way:

double a = 0.123456789123456789d;
float b = (float)a;
float c = Convert.ToSingle(a);
bool areBothSame = b == c;
Console.WriteLine("b == c: "areBothSame);
//Console Output:
//b == c: true

What Convert.ToSingle() does is that:

public static float ToSingle(double value)
{
    return (float)value;
}

So doesn't really maters what you prefer, it does the same job.