C＃-是否基于ASCII值进行类型转换（将数字转换为char）？

Question

I'm new to C#, and I'm trying to understand more about data types and conversion. I have the following console program:

using System;

namespace First_lesson
{
    class Program
    {
        static void Main(string[] args)
        {
            char singleLetter = 'B';
            short num = 291;
            Console.WriteLine("{0} {1}", num, singleLetter);


            singleLetter = Convert.ToChar(num);
            Console.WriteLine(singleLetter);
            Console.WriteLine("{0} {1}", sizeof(short), sizeof(char));

        }
    }
}

I don't understand why, when I convert num to a char , I get a lowercase g instead of the hashtag symbol # .

Isn't the conversion made based on ASCII values?

Answer 1

Convert.ToChar returns a char (which is a UTF-16 code unit) that has the specified numeric value.

291 (decimal) is the same as 0x123 (hex), so Convert.ToChar(291) returns a char containing the character U+0123 , which is LATIN SMALL LETTER G WITH CEDILLA, ie, ģ .

When you print this to a non-Unicode console, the accent is stripped off and an ASCII g is printed instead.

Answer 2

The char keyword is used to declare an instance of the System.Char structure that the .NET Framework uses to represent a Unicode character. The value of a Char object is a 16-bit numeric (ordinal) value.

Actually, one char represents a Unicode character. 35 in decimal is the representation of # sign

public static void Main()
{
    char singleLetter = 'B';
    short num = 35;
    Console.WriteLine("{0} {1}", num, singleLetter);

    singleLetter = Convert.ToChar(num);
    Console.WriteLine(singleLetter);
    Console.WriteLine("{0} {1}", sizeof(short), sizeof(char));
    Console.ReadLine();
}

Try this:

short singleLetter = Convert.ToInt16('B');
Console.WriteLine(singleLetter);

B is the 66 decimal value You can use this page as a reference for the Unicode table