[英]ASP.NET C# Set OnSelectedIndexChanged from Code Behind
[英]C# ASP.NET Selecting multiple column from same mysql command and use them in code behind
我会做这件事:
"select nome,cognome from Utenti where CodiceCliente = @codice"
然后在后面的代码中使用“ nome”中的值和“ cognome”中的值。 与PHP有关联数组,在C#ASP.NET中?
到目前为止,我一直使用两个不同的命令,但是现在很烦人。
例:
MySqlCommand getNome = new MySqlCommand("select Nome from Utenti where CodiceCliente = @codice", userConnection);
MySqlCommand getCognome = new MySqlCommand("select Cognome from Utenti where CodiceCliente = @codice", userConnection);
MySqlCommand getEmail = new MySqlCommand("select IndirizzoEmail from Utenti where CodiceCliente = @codice", userConnection);
getNome.Parameters.AddWithValue("@codice", codice);
getCognome.Parameters.AddWithValue("@codice", codice);
getEmail.Parameters.AddWithValue("@codice", codice);
userConnection.Open();
string nome = Convert.ToString(getNome.ExecuteScalar());
string cognome = Convert.ToString(getCognome.ExecuteScalar());
string email = Convert.ToString(getEmail.ExecuteScalar());
你能帮助我吗?
以前谢谢
丹尼尔
简单用法:
using(var connection = new MySqlConnection(myConnString))
{
var cmd = connection.CreateCommand();
cmd.CommandText = "select nome,cognome from Utenti where CodiceCliente = @codice";
cmd.Parameters.AddWithValue("@codice", value);
var reader = cmd.ExecuteReader();
while(reader.Read())
{
// here could be problems if database value is null
var nome = reader["nome"];
var cognome = reader["cognome"];
}
}
您可以尝试以下方法:
using(var connection = new MySqlConnection(myConnString))
{
var cmd = connection.CreateCommand();
cmd.CommandText = "select nome,cognome from Utenti where CodiceCliente = @codice";
cmd.Parameters.AddWithValue("@codice", value);
var reader = cmd.ExecuteReader();
if(reader.HasRows) {
while(reader.Read())
{
var nome = reader[0];
var cognome = reader[1];
}
reader.Close();
}
}
您必须检查DataReader
是否有行以避免异常,最后不要忘记关闭它
声明:本站的技术帖子网页,遵循CC BY-SA 4.0协议,如果您需要转载,请注明本站网址或者原文地址。任何问题请咨询:yoyou2525@163.com.