对UTF8编码和ASCII编码文件读写的小测试

来源：互联网发布：编c语言用什么软件编辑：程序博客网时间：2024/06/10 09:32

using System;
using System.Collections.Generic;
using System.Text;
using System.IO;

namespace ch04
{
    class Program
    {
        static string str_ascii = @"g:/testASCII.xml";
        static string str_utf8 = @"g:/testUTF8.xml";
        static void Main(string[] args)
        {
            Program.TestSaveUTF8();
            Program.TestSaveASCII();

            /*
             * 用UTF8编码的StreamReader读取ASCII编码的文件，读出来的汉字字符不能识别
             * 用UTF8编码的StreamReader读取UTF8编码的文件，读出来的汉字字符能识别
             * 用ASCII编码的StreamReader读取ASCII编码的文件，读出来的汉字字符不能识别
             * 用ASCII编码的StreamReader读取UTF8编码的文件，读出来的汉字字符能识别
             *
             * 总之，用UTF8编码存储的文件，无论用何种编码方式读取，都能正确识别其中的汉字
             * 而用ASCII编码存储的文件，无论用何种编码方式读取，都不能正确识别其中的汉字
             *
             */
            Program.TestReadUTF8(str_ascii);
            Program.TestReadUTF8(str_utf8);
            Program.TestReadASCII(str_ascii);
            Program.TestReadASCII(str_utf8);
        }
        static void TestSaveASCII()
        {
            string text = "<?xml version=/"1.0/"?>/n" + "<HEAD>head 测试一下</HEAD>/n";
            using (FileStream fs = new FileStream(str_ascii, FileMode.OpenOrCreate, FileAccess.Write))
            {
                using (StreamWriter sr = new StreamWriter(fs,Encoding.ASCII))
                {
                    sr.Write(text);
                }
            }
        }
        static void TestSaveUTF8()
        {
            string text = "<?xml version=/"1.0/"?>/n" + "<HEAD>head 测试一下</HEAD>/n";
            using (FileStream fs = new FileStream(str_utf8, FileMode.OpenOrCreate, FileAccess.Write))
            {
                using (StreamWriter sr = new StreamWriter(fs, Encoding.UTF8))
                {
                    sr.Write(text);
                }
            }
        }
        static void TestReadUTF8(string path)
        {
            Console.WriteLine("Reading "+path);
            using (FileStream fs = new FileStream(path, FileMode.Open, FileAccess.Read))
            {
                using (StreamReader sr = new StreamReader(fs, Encoding.UTF8))
                {
                    string str = sr.ReadToEnd();
                    foreach (char s in str.ToCharArray())
                    {
                        Console.Write("{0}", s);
                    }
                }
            }
            Console.WriteLine("Read end!");
        }
        static void TestReadASCII(string path)
        {
            Console.WriteLine("Reading " + path);
            using (FileStream fs = new FileStream(path, FileMode.Open, FileAccess.Read))
            {
                using (StreamReader sr = new StreamReader(fs, Encoding.ASCII))
                {
                    string str = sr.ReadToEnd();
                    foreach (char s in str.ToCharArray())
                    {
                        Console.Write("{0}", s);
                    }
                }
            }
            Console.WriteLine("Read end!");
        }
    }
}