[CSharpTips]C#读取SQLite数据库中文乱码

C#读取SQLite数据库中文乱码

C#在读取C++写入数据的Sqlite数据库中的Text内容时，会出现乱码，因为C++默认编码格式为GB2312，而Sqlite编码格式为UTF-8，存入时不统一就会出现乱码

using System;
using System.Data;
using System.Data.SQLite;
using System.Text;

namespace SQLiteSamples
{
    class Program
    {
        //数据库连接
        SQLiteConnection m_dbConnection;

        static void Main(string[] args)
        {
            Program p = new Program();
            //sql中使用hex(Text)将Text转换为16进制字符串
            DataTable table = p.GetData("select hex(Name) from highscores");
            var name = table.Rows[0][0].ToString();
            byte[] byteresult = p.HexStringToByteArrart(name);
            //读取C++写入的sqlite数据库中的Text，将byte数组解析为GB2312编码字符串
            //var result = Encoding.GetEncoding("GB2312").GetString(byteresult);
            //将byte数组解析为UTF-8编码字符串
            var result = Encoding.GetEncoding("UTF-8").GetString(byteresult);
            Console.WriteLine(result);
            Console.ReadLine();

        }
        public Program()
        {
            createNewDatabase();
            connectToDatabase();
            createTable();
            fillTable();
            printHighscores();
        }

        //创建一个空的数据库
        void createNewDatabase()
        {
            SQLiteConnection.CreateFile("MyDatabase.sqlite");
        }

        //创建一个连接到指定数据库
        void connectToDatabase()
        {
            m_dbConnection = new SQLiteConnection("Data Source=MyDatabase.sqlite;Version=3;");
            m_dbConnection.Open();
        }

        //在指定数据库中创建一个table
        void createTable()
        {
            string sql = "create table highscores (name varchar(20), score int)";
            SQLiteCommand command = new SQLiteCommand(sql, m_dbConnection);
            command.ExecuteNonQuery();
        }

        //插入一些数据
        void fillTable()
        {
            string sql = "insert into highscores (name, score) values ('张三', 3000)";
            SQLiteCommand command = new SQLiteCommand(sql, m_dbConnection);
            command.ExecuteNonQuery();

            sql = "insert into highscores (name, score) values ('李四', 6000)";
            command = new SQLiteCommand(sql, m_dbConnection);
            command.ExecuteNonQuery();

            sql = "insert into highscores (name, score) values ('王五', 9001)";
            command = new SQLiteCommand(sql, m_dbConnection);
            command.ExecuteNonQuery();
        }

        //使用sql查询语句，并显示结果
        void printHighscores()
        {
            string sql = "select * from highscores order by score desc";
            SQLiteCommand command = new SQLiteCommand(sql, m_dbConnection);
            SQLiteDataReader reader = command.ExecuteReader();
            while (reader.Read())
                Console.WriteLine("Name: " + reader["name"] + "\tScore: " + reader["score"]);
            //Console.ReadLine();
        }
        /// <summary>
        /// 将查询结果填充至DataTable
        /// </summary>
        /// <param name="sql"></param>
        /// <returns></returns>
        DataTable GetData(string sql)
        {
            DataTable dt = new DataTable();
            lock (m_dbConnection)
            {
                SQLiteDataAdapter adapter = new SQLiteDataAdapter(sql, m_dbConnection);
                adapter.Fill(dt);
                return dt;
            }
        }
        /// <summary>
        /// 将16进制字符串转换为byte数组
        /// </summary>
        /// <param name="input"></param>
        /// <returns></returns>
        byte[] HexStringToByteArrart(string input)
        {
            input = input.Replace(" ", "").Trim().ToUpper();
            byte[] buffer = new byte[input.Length / 2];
            for (int i = 0; i < input.Length; i += 2)
            {
                buffer[i / 2] = (byte)Convert.ToByte(input.Substring(i, 2), 16);
            }
            return buffer;
        }
    }
}