发布：2019/11/12 11:34:15作者：管理员 来源：本站 浏览次数：958

测试环境

.net 4.6

vs2015

mvc5

sqlserver2008

1.数据库

CREATE TABLE [dbo].[CarInfo](
[ID] [int] IDENTITY(1,1) NOT NULL,
[CarNo] [varchar](50) NOT NULL,
[Lng] [varchar](50) NOT NULL,
[Lat] [varchar](50) NOT NULL,
[LocDt] [datetime] NOT NULL,
 CONSTRAINT [PK_CarInfo] PRIMARY KEY CLUSTERED
(
[ID] ASC
)WITH (PAD_INDEX  = OFF, STATISTICS_NORECOMPUTE  = OFF, IGNORE_DUP_KEY = OFF, ALLOW_ROW_LOCKS  = ON, ALLOW_PAGE_LOCKS  = ON) ON [PRIMARY]
) ON [PRIMARY]
GO

数据库要使用service broker

ALTER DATABASE DBName SET NEW_BROKER WITH ROLLBACK IMMEDIATE;
ALTER DATABASE DBName SET ENABLE_BROKER;

初始化数据库

INSERT INTO CARINFO (CARNO,LNG,LAT,LOCDT) VALUES ('豫A12345','113.123','43.123',GETDATE())


2.新建MVC项目

安装SignalR包

Install-Package Microsoft.AspNet.SignalR

修改startup.cs

    public partial class Startup
    {
        public void Configuration(IAppBuilder app)
        {
            ConfigureAuth(app);
            app.MapSignalR();
        }
    }

修改web.config，增加数据库连接字符串

    <add name="ConnString" connectionString="data source=.;initial catalog=MySignalR;persist security info=True;user id=sa;password=yourpass;" providerName="System.Data.SqlClient" />

增加数据模

    public class CarInfo
    {
        public int ID { get; set; }


        public string CarNo { get; set; }


        public string Lng { get; set; }


        public string Lat { get; set; }


        public DateTime LocDt { get; set; }
    }

新建类

    public class CarInfoHub : Microsoft.AspNet.SignalR.Hub
    {
        public static void Show()
        {
            IHubContext context = GlobalHost.ConnectionManager.GetHubContext<CarInfoHub>();
            context.Clients.All.displayStatus();
        }
    }

业务实现

    public class CarInfoRepository
    {
        public CarInfo GetData(int id)
        {
            using (var connection = new SqlConnection(ConfigurationManager.ConnectionStrings["ConnString"].ConnectionString))
            {
                connection.Open();
                using (SqlCommand command = new SqlCommand($"SELECT [ID],[CarNo],[Lng],[Lat],[LocDt] FROM [dbo].[CarInfo] WHERE ID = {id}", connection))
                {
                    command.Notification = null;


                    SqlDependency dependency = new SqlDependency(command);
                    dependency.OnChange += dependency_OnChange;


                    if (connection.State == ConnectionState.Closed)
                        connection.Open();


                    using (var reader = command.ExecuteReader())
                    {
                        while (reader.Read())
                        {
                            return new CarInfo()
                            {
                                ID = reader.GetInt32(0),
                                CarNo = reader.GetString(1),
                                Lng = reader.GetString(2),
                                Lat = reader.GetString(3),
                                LocDt = reader.GetDateTime(4)
                            };
                        }
                    }
                }
            }


            return null;
        }


        private void dependency_OnChange(object sender, SqlNotificationEventArgs e)
        {
            CarInfoHub.Show();
        }
    }

修改Global.asax

        protected void Application_Start()
        {
            GlobalConfiguration.Configure(WebApiConfig.Register);
            SqlDependency.Start(ConfigurationManager.ConnectionStrings["ConnString"].ConnectionString);


            AreaRegistration.RegisterAllAreas();
            FilterConfig.RegisterGlobalFilters(GlobalFilters.Filters);
            RouteConfig.RegisterRoutes(RouteTable.Routes);
            BundleConfig.RegisterBundles(BundleTable.Bundles);
        }


        protected void Application_End(object sender, EventArgs e)
        {
            SqlDependency.Stop(ConfigurationManager.ConnectionStrings["ConnString"].ConnectionString);
        }

新建API

    public class DefaultController : ApiController
    {
        readonly CarInfoRepository _repository = new CarInfoRepository();


        // GET api/values
        public CarInfo Get(int id)
        {
            return _repository.GetData(id);
        }
    }

修改控制器

        public ActionResult Index()
        {

//这里只是测试功能，指定了车辆编号
            ViewBag.ID = 1;
            return View();
        }

修改视图

@{
    Layout = null;
}


<!DOCTYPE html>


<html>
<head>
    <meta name="viewport" content="width=device-width" />
    <title>车辆实时跟踪</title>
    <script src="~/Scripts/jquery-1.10.2.min.js"></script>
    <script src="~/Scripts/jquery.signalR-2.2.1.min.js"></script>
    <script src="~/signalr/hubs" type="text/javascript"></script>
    <script type="text/javascript">
        var maxID;
        $(function () {
            var CarID = @ViewBag.ID;
            // Proxy created on the fly
            var job = $.connection.carInfoHub;


            // Declare a function on the job hub so the server can invoke it
            job.client.displayStatus = function () {
                getData();
            };


            // Start the connection
            $.connection.hub.start();
            getData();
        });


        function getData() {
            var $tbl = $('#tblJobInfo');
            $.ajax({
                url: '../api/Default/'+CarID,
                type: 'GET',
                datatype: 'json',
                success: function (data) {
                    $tbl.empty();
                    $tbl.append(' <tr><th>ID</th><th>CarNo</th><th>Lng</th><th>Lat</th></tr>');
                    var str ='<tr><td>' + data.ID + '</td><td>' + data.CarNo + '</td><td>' + data.Lng + '</td><td>' + data.Lat + '</td></tr>';
                    $tbl.append(str);
                }
            });
        }
    </script>
</head>
<body>
    <div>
        <table id="tblJobInfo" style="text-align: center; margin-left: 10px">
        </table>
    </div>
</body>
</html>

现在测试一下

update carinfo set
Lng = CAST(Lng as float)+0.0001,
Lat = CAST(Lat as float)+0.0001,
LocDt = getdate();

面页数据可以实时发生变化。

下一步：实现车辆定位地图。到下一周再作。
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