只读:SqlDataRead
或者:DataSet
例:string mySelectQuery = "SELECT * FROM table";
SqlConnection myConnection = new SqlConnection(myConnString);
SqlCommand myCommand = new SqlCommand(mySelectQuery,myConnection);
myConnection.Open();
SqlDataReader myReader;
myReader = myCommand.ExecuteReader(); while (myReader.Read()) {
//do something
}
or:
DataSet oDs=new DataSet();
SqlDataAdapter oDa=new SqlDataAdapter(mySelectQuery,myConnection);
oDa.Fill(oDs,"table");
或者:DataSet
例:string mySelectQuery = "SELECT * FROM table";
SqlConnection myConnection = new SqlConnection(myConnString);
SqlCommand myCommand = new SqlCommand(mySelectQuery,myConnection);
myConnection.Open();
SqlDataReader myReader;
myReader = myCommand.ExecuteReader(); while (myReader.Read()) {
//do something
}
or:
DataSet oDs=new DataSet();
SqlDataAdapter oDa=new SqlDataAdapter(mySelectQuery,myConnection);
oDa.Fill(oDs,"table");
namespace HowTo.Samples.ADONET
{using System;
using System.Data;
using System.Data.SqlClient;public class adooverview3
{
public static void Main()
{
adooverview3 myadooverview3 = new adooverview3();
myadooverview3.Run();
} public void Run()
{
SqlDataReader myReader = null;
SqlConnection mySqlConnection = new SqlConnection("server=(local)\\NetSDK;Trusted_Connection=yes;database=northwind");
SqlCommand mySqlCommand = new SqlCommand("select * from customers", mySqlConnection); try
{
mySqlConnection.Open();
myReader = mySqlCommand.ExecuteReader(); Console.Write("客户 ID ");
Console.WriteLine("公司名称"); while (myReader.Read())
{
Console.Write(myReader["CustomerId"].ToString() + " ");
Console.WriteLine(myReader["CompanyName"].ToString());
}
}
catch(Exception e)
{
Console.WriteLine(e.ToString());
}
finally
{
if (myReader != null)
myReader.Close(); if (mySqlConnection.State == ConnectionState.Open)
mySqlConnection.Close();
}
}
}}其中myReader就是读出来的纪录。
SqlConnection myConnection = new SqlConnection(myConnString);
SqlCommand myCommand = new SqlCommand(mySelectQuery,myConnection);
myConnection.Open();
DataSet oDs=new DataSet();
SqlDataAdapter oDa=new SqlDataAdapter(mySelectQuery,myConnection);
oDa.Fill(oDs,"table");
DataTable YourTable=oDa.Tables[0]
Connection.Open();
string str;
str=com.ExecuteScalar().ToString();//返回一个值,如果是其他数据类型再转换