Database Operation connection Additions and deletions change check disconnect

Traditional way

Encapsulating database Operations as a tool class

using System.Data;using System.Data.SqlClient;public class TraditionalSQLServerDBManager{    SqlConnection con;    public TraditionalSQLServerDBManager()    {        con = new SqlConnection();        con.ConnectionString = "Server=;DataBase=;Uid=;pwd=;";        con.Open();     }    public void ExcuteSQL(string sql)    {        SqlCommand com = new SqlCommand();        com.Connection = con;        com.CommandType = CommandType.Text;        com.CommandText = sql;        SqlDataReader dr = com.ExecuteReader();//执行SQL语句        dr.Close();//关闭执行        con.Close();//关闭数据库     }}

Using the tool class

TraditionalSQLServerDBManager manager = new TraditionalSQLServerDBManager();manager.ExcuteSQL(@"INSERT INTO [test2].[dbo].[BitTable] ([IsDelete]) VALUES(1)");

Using third-party libraries Dapper

Package Tool Class

public class DbManager<T> where T : class{    private static DbManager<T> instance;    private static object _lock = new object();    private SqlConnection connection;    public static DbManager<T> Instance    {        get        {            lock (_lock)            {                if (instance == null)                {                    instance = new DbManager<T>();                }             }            return instance;        }    }    public DbManager()    {        connection = new SqlConnection("Server=;DataBase=;Uid=;pwd=;");        connection.Open();    }    public IEnumerable<T> QueryBySQL(string sql)    {        return connection.Query<T>(sql);    }    public bool ExecuteOne(string sql)    {        if (connection.Execute(sql) != 0)            return true;        return false;    }}

Calling methods

List<BitModel> list = new BLL.AboutDBManager().GetBitModel();

Connect to other databases, reference the target database related DLLs, and change SqlConnection to target connection.
Such as:

using System.Data.SQLite;private SQLiteConnection connection;

Other

A number of different database connections, such as Mysql,sql Server,oracle, may consider using interfaces to achieve polymorphic

Database Operation connection Additions and deletions change check disconnect