为什么 char.GetNumericValue() 给出错误的结果？

Question

I have the following enum

public enum Status
{
    New = 'N',
    Live = 'L',
    Expired = 'E'
}

And upon receiving the char 'N' I would like to get the relevant value (ie Status.New )

It seems that Enum.Parse will not work with char , or even char.toString() for that matter, so I want to get the numeric value associated with the char

var myChar = 'N';
var myNumber = Char.GetNumericValue(myChar); // or char.GetNumericValue(myChar);

and the value of myNumber is -1 , which is incorrect

What is going on?

Answer 1

The Microsoft documentation says that Char.GetNumericValue() converts a specified numeric Unicode character to a double-precision floating-point number .

The character 'N' is not numeric, it is an alphabetical character.

If you want to get a Status enum value, you could just use:

Status status = (Status)myChar;

Answer 2

The documentation says GetNumericValue() returns: "The numeric value of c if that character represents a number ; otherwise, -1.0."
'N' does not represent a number, so it returns -1.

A char can be implicitly converted to a number:

int number = 'N';

Or, if you want to use var , you just need an explicit cast.

Note also that your enum values are int s, not char s. They are implicitly converted.