c# 对数据库的操作

1.首先需要引用

using System.Data.SqlClient;

2.创建连接

SqlConnection connection = new SqlConnection();
connection.ConnectionString = "Data Source= IP地址; Initial Catalog = 数据库名称; User ID = 数据库用户名; Password=密码";
connection.Open(); //开启连接

3.执行操作

数据库表名称：Test 参数：ID(主键)，Name，Age

 //添加数据
private void button1_Click(object sender, EventArgs e)
{
    SqlCommand command = new SqlCommand("insert into Test(ID,Name,Age) values (2,'王五','23')", connection);
    command.ExecuteNonQuery();  //执行指令并返回影响行数
}

//修改数据
private void button2_Click(object sender, EventArgs e)
{
    SqlCommand command = new SqlCommand("update Test set Name = '哎呦',Age = '100' where ID=1",connection);
    command.ExecuteNonQuery();
}

//删除数据
private void button3_Click(object sender, EventArgs e)
{
   SqlCommand command = new SqlCommand("delete Test where ID = 1",connection);
   command.ExecuteNonQuery();
}

 4.读取数据

SqlDataReader reader = command.ExecuteReader();
if (reader.HasRows)   //判断是否有数据
{
    while (reader.Read())
    {
        MessageBox.show(reader[0].toString());
    }
}