Ado.net SQL连接

Question

I try to make Sql connection using Ado.Net. I create a ConsoleApplication and get the Name and UnitPrice values from my database. After execution Console says can not open a connection. What is wrong that I make ?

Here is my code:

using System;
using System.Collections.Generic;
using System.Data.SqlClient;
using System.Linq;
using System.Text;
using System.Threading.Tasks;

class ConsoleApplication1
{
    static void Main()
    {
        string connectionString =
            "Data Source=EMINCIFTCI/EMIN;Initial Catalog=Ado;User ID=sa;Password=10203040";


        string queryString =
            "SELECT Name, UnitPrice from dbo.Product "   
                + "ORDER BY UnitPrice DESC;";

        using (SqlConnection connection =
            new SqlConnection(connectionString))
        {

            SqlCommand command = new SqlCommand(queryString, connection);

            try
            {
                connection.Open();
                SqlDataReader reader = command.ExecuteReader();
                while (reader.Read())
                {
                    Console.WriteLine("\t{0}\t{1}",
                        reader[0], reader[1]);
                }
                reader.Close();
            }
            catch (Exception ex)
            {
                Console.WriteLine(ex.Message);
            }
            Console.ReadLine();
        }
    }
}

Answer 1

Assuming EMINCIFTCI/EMIN is your computer name and (I assume) SQL Server instance, you need to swap the forward slash with a backslash (two, technically, unless you use a verbatim string).

So, use either

string connectionString =
            "Data Source=EMINCIFTCI\\EMIN;Initial Catalog=Ado;User ID=sa;Password=10203040";

or

string connectionString =
            @"Data Source=EMINCIFTCI\EMIN;Initial Catalog=Ado;User ID=sa;Password=10203040";

You may want to review https://www.connectionstrings.com/

Answer 2

I think the connection string should be proper "Data Source=EMINCIFTCI/EMIN;Initial Catalog=Ado;User ID=sa;Password=10203040;"

There should be semicolon in the end