在c#中从MSSQL输出列的内容

using System;
using System.Data.SqlClient;

class Program
{
    static void Main()
    {
        string connectionString = "Data Source=YourServerName;Initial Catalog=YourDatabaseName;User ID=YourUsername;Password=YourPassword";
        string query = "SELECT columnName FROM tableName";

        using (SqlConnection connection = new SqlConnection(connectionString))
        {
            SqlCommand command = new SqlCommand(query, connection);
            connection.Open();

            SqlDataReader reader = command.ExecuteReader();

            while (reader.Read())
            {
                string columnValue = reader.GetString(0);
                Console.WriteLine(columnValue);
            }

            reader.Close();
        }
    }
}