将C＃连接到SQL Server Compact数据库

Question

Hi I'm trying to connect an SQL server compact database to my program and I want a button that deletes all entries from the database, when I Press said button the program throws an exception and gives the following error message "A network-related or instance-specific error occurred while establishing a connection to SQL Server. The server was not found or was not accessible. Verify that the instance name is correct and that SQL Server is configured to allow remote connections. (provider: SQL Network Interfaces, error: 26 - Error Locating Server/Instance Specified)"

Help Please? =]

Sorry, Code is Below =]

using System;
using System.Collections.Generic;
using System.ComponentModel;
using System.Data;
using System.Drawing;
using System.Linq;
using System.Text;
using System.Windows.Forms;
using System.Data.SqlClient;
using System.Data.SqlServerCe;


namespace Booking_system_Final
{
    public partial class PendingJobs : Form
    {
        SqlConnection sc = new SqlConnection("Data Source=C:\\Users\\Administrator\\My Documents\\BMS_Data.sdf");
        public PendingJobs()
        {
            InitializeComponent();
        }

        private void PendingJobs_Load(object sender, EventArgs e)
        {
            // TODO: This line of code loads data into the 'bMSDataSet.Bookings' table. You can move, or remove it, as needed.
            this.bookingsTableAdapter.Fill(this.bMSDataSet.Bookings);
            // TODO: This line of code loads data into the 'bMS_DataDataSet1.Bookings' table. You can move, or remove it, as needed.


        }

        private void button1_Click(object sender, EventArgs e)
        {
            sc.Open();
            SqlCommand cmd = new SqlCommand("DELETE FROM Bookings");
            cmd.Connection = sc;
            cmd.ExecuteNonQuery();
            sc.Close();
            MessageBox.Show("Database Cleared");


        }
    }
}

Answer 1

Try use SqlCeConnection class rather than SqlConnection :

SqlCeConnection sqlConnection1 = new SqlCeConnection();
sqlConnection1.ConnectionString = "Data Source = C:\\Users\\Administrator\\My Documents\\BMS_Data.sdf;Persist Security Info=False";

Answer 2

如果要连接到SQL Server Compact，请使用SqlCeConnection，SqlCeCommand等。添加对SQL Server Compact ADO.NET提供程序的引用，System.Data.SqlServerCe.dll

Answer 3

Have a look at this blog article: SQL SERVER – FIX : ERROR : (provider: Named Pipes Provider, error: 40 – Could not open a connection to SQL Server)

This goes step-by-step through what you might need to do:

In short:

1. SQL Server should be up and running.
2. Enable TCP/IP in SQL Server Configuration
3. Open Port in Windows Firewall
4. Enable Remote Connection
5. Enable SQL Server Browser Service
6. Create exception of sqlbrowser.exe in Firewall
7. Recreate Alias

About the where and what to do in each step, you will find more in-depth information in the article.

You may also want to have a look at the Connection strings for SQL Server Compact . There you can find other variations of the connection string you could try to play with.

Answer 4

You seems to be using a bad connection string. (Or the file path is wrong). Check out http://www.connectionstrings.com/sql-server-ce for connection string options.