.net数据库程序源码

using System;
using System.Data.SqlClient;

class Program
{
    static void Main()
    {
        string connectionString = "Server=your_server;Database=your_database;User Id=your_user;Password=your_password;";
        try
        {
            using (SqlConnection connection = new SqlConnection(connectionString))
            {
                connection.Open();
                Console.WriteLine("数据库连接成功！");
            }
        }
        catch (Exception ex)
        {
            Console.WriteLine("数据库连接失败：" + ex.Message);
        }
    }
}

using System;
using System.Data.SqlClient;

class Program
{
    static void Main()
    {
        string connectionString = "Server=your_server;Database=your_database;User Id=your_user;Password=your_password;";
        try
        {
            using (SqlConnection connection = new SqlConnection(connectionString))
            {
                connection.Open();
                string query = "SELECT * FROM your_table WHERE some_column = @value";
                using (SqlCommand command = new SqlCommand(query, connection))
                {
                    command.Parameters.AddWithValue("@value", "some_value");
                    using (SqlDataReader reader = command.ExecuteReader())
                    {
                        while (reader.Read())
                        {
                            Console.WriteLine(reader["some_column"].ToString());
                        }
                    }
                }
            }
        }
        catch (Exception ex)
        {
            Console.WriteLine("查询执行失败：" + ex.Message);
        }
    }
}