c# 数据库获取数据

以下是使用C#获取数据库数据的示例代码：

using System;
using System.Data.SqlClient;

class Program
{
    static void Main()
    {
        string connectionString = "Data Source=serverName;Initial Catalog=databaseName;User ID=userName;Password=password";
        
        using (SqlConnection connection = new SqlConnection(connectionString))
        {
            connection.Open();
            
            string query = "SELECT * FROM tableName";
            
            SqlCommand command = new SqlCommand(query, connection);
            
            SqlDataReader reader = command.ExecuteReader();
            
            while (reader.Read())
            {
                // 从数据库中获取数据
                int id = (int)reader["id"];
                string name = (string)reader["name"];
                DateTime date = (DateTime)reader["date"];
                
                // 处理数据
                Console.WriteLine("ID: " + id);
                Console.WriteLine("Name: " + name);
                Console.WriteLine("Date: " + date);
                Console.WriteLine();
            }
            
            reader.Close();
        }
    }
}

请注意，上述代码中的`serverName`、`databaseName`、`userName`、`password`和`tableName`需要根据实际情况进行替换。