求C#连接数据库完整代码

                    string sqlconn = "Data Source=.;Initial Catalog=表名;Integrated Security=True";
                    
                    SqlConnection conn = new SqlConnection(sqlconn);
 

http://blog.，仅供参考!

private int SetHasEst()
        {
            string conString;

            SqlConnection sqlcon = new SqlConnection(@"Server = PC--20110803JXD\SQLEXPRESS;Database = Mltmd;User ID=sa;Password='wfl137632'");

            SqlCommand cmd = new SqlCommand();
            cmd.Connection = sqlcon;

            int i = 1;  //1连接数据库成功,0失败

            try
            {
                sqlcon.Open();
                this.con.Open();

                conString = "SELECT * FROM Picture WHERE ghtpcd=" + "'" + this.tbZhtCd.Text.Trim() + "'";
                 = conString;
                this.picHasEst = this.getExsRows(cmd);

                conString = "SELECT * FROM Document WHERE ghtpcd=" + "'" + this.tbZhtCd.Text.Trim() + "'";
                 = conString;
                this.docHasEst = this.getExsRows(cmd);

                conString = "SELECT * FROM Record WHERE ghtpcd=" + "'" + this.tbZhtCd.Text.Trim() + "'";
                 = conString;
                this.audHasEst = this.getExsRows(cmd);

                conString = "SELECT * FROM Video WHERE ghtpcd=" + "'" + this.tbZhtCd.Text.Trim() + "'";
                 = conString;
                this.vidHasEst = this.getExsRows(cmd);

                conString = "SELECT * FROM Chart WHERE ghtpcd=" + "'" + this.tbZhtCd.Text.Trim() + "'";
                 = conString;
                this.chtHasEst = this.getExsRows(cmd);
            }
            catch (Exception ex)
            {
                MessageBox.Show(ex.Message, "错误", MessageBoxButtons.OK, MessageBoxIcon.Error);

                i = 0;
            }
            finally
            {
                sqlcon.Close();
            }

            return i;
        }

private void loadProvince()
        {
            SqlCommand cmd = new SqlCommand();
            cmd.Connection = this.con;  //private SqlConnection con=new SqlConnection(@"Server = PC--20110803JXD\SQLEXPRESS;Database = Dsdv;User ID=sa;Password='wfl137632'");
             = "SELECT dsdvsn,dsdvcd FROM dsdv WHERE dsdvcd LIKE '__0000000000000'";

            SqlDataReader dr = cmd.ExecuteReader();

            while (dr.Read())
            {
                this.cbProvince.Items.Add(dr[0]);
                this.pvcdlist.Add(dr[1]);
            }

            dr.Close();
        }

系统身份登录：
Data Source=.;Initial Catalog=表名;Integrated Security=True



账户密码登录：
server=.;uid=登录名;pwd=密码;database=数据库名称

sql 无密 string host, string db, bool Security
Data Source=;Initial Catalog=?;Integrated Security=True
sql 有密 string host,string db,string usr, string pwd
Data Source=;Initial Catalog=?;UID=?;PassWord=?

acess 无密 string file
Provider=Microsoft.Jet.OLEDB.4.0;Data Source=?
acess 有密 string file, string pwd
Provider=Microsoft.Jet.OLEDB.4.0;Data Source=?;Jet OLEDB:Database Password=?


oracle  string ip, int port, string db, string user, string pwd
 "Data Source = ( DESCRIPTION =" +
                "( ADDRESS_LIST = (ADDRESS = (PROTOCOL=TCP)(HOST=?)(PORT=?)))" +
                "(CONNECT_DATA=(SERVER=DEDICATED)(SERVICE_NAME=?)));" +
                "User Id=?;Password=?;";