C# 如何知道sql server asp.net中的行值?
我几天前发布了这个 我得到了这个答案C# 如何知道sql server asp.net中的行值?,c#,asp.net,sql-server,C#,Asp.net,Sql Server,我几天前发布了这个 我得到了这个答案 SqlCommand cmdEvent = new SqlCommand("SELECT COUNT(date) FROM patients WHERE date= '2012/02/23'", yourSqlConnection); object myCount; if (yourSqlConnection.State == ConnectionState.Closed){ yourSqlConnection.Open(); } myCount = cmd
SqlCommand cmdEvent = new SqlCommand("SELECT COUNT(date) FROM patients WHERE date= '2012/02/23'", yourSqlConnection);
object myCount;
if (yourSqlConnection.State == ConnectionState.Closed){ yourSqlConnection.Open(); }
myCount = cmdEvent.ExecuteScalar();
if (yourSqlConnection.State == ConnectionState.Open){ yourSqlConnection.Close(); }
if (myCount != null)
{
if ((int)myCount >= 10)
{
// Logic here e.g myLabel.Text = "You have reached your maximum of 10 visits!";
return;
}
}
但是现在我不需要一行的值,而是需要知道两行的值,我不知道怎么做。
我正在尝试进行登录,我需要用户id以使会话唯一,但我还需要验证该查询是否返回true,我按照以下步骤进行了操作:
comando = new SqlCommand("SELECT user_name FROM login WHERE user_name=@user AND pass=@pass", conexion);
comando.Parameters.AddWithValue("@pass", Upass);
comando.Parameters.AddWithValue("@user", user);
object check_coincidence = comando.ExecuteScalar();
if ((string)check_coincidence == user)
{
Session["USER"] = check_coincidence;
Response.Redirect("someURL")
}
但我不知道如何使用用户ID使会话唯一,我的意思是,将该值作为新会话。要从查询中获得更多结果,必须使用SqlReader
comando = new SqlCommand("SELECT user_name, user_id FROM login WHERE user_name=@user AND pass=@pass", conexion);
comando.Parameters.AddWithValue("@pass", Upass);
comando.Parameters.AddWithValue("@user", user);
SqlDataReader reader = commando.ExecuteReader();
while (reader.Read())
{
var userName = Convert.ToString(reader["user_name"]);
var userId = Convert.ToInt32(reader["user_id"]);
}
我建议大家遵循一些关于这方面的教程,这将有助于理解Sql类。检查一下这个例子:THANX MEN!!我真的很感激!