C#曲线分析平台的制作（六，Sqldependency+Signalr+windows 服务）

在经过五天的学习和资料收集后，终于初步实现了利用sqldependency进行数据库变化监控，signalr进行前后台交互，数据实时更新。下面将源代码贴出进行初步分析：

1.系统整体框架构成：

2.具体代码分析：

1.signalr交互（利用persistence connection）

a.新建web程序

b.引入Signalr(通过nuget包引入）

c.使用persistence connection模式（当然也可以使用Hub模式）

1.新建persistence connection类

using System;

using System.Collections.Generic;

using System.Linq;

using System.Threading.Tasks;

using System.Web;

using Microsoft.AspNet.SignalR;

public class MyConnection1 : PersistentConnection

{

    protected override Task OnConnected(IRequest request, string connectionId)

    {

        return Connection.Send(connectionId, "Welcome!");

    }

    protected override Task OnReceived(IRequest request, string connectionId, string data)

    {

        return Connection.Broadcast(data);

    }

}

2.新建owin startup路由文件（startup.cs）

using System;

using System.Threading.Tasks;

using Microsoft.Owin;

using Owin;

[assembly: OwinStartup(typeof(Startup))]

public class Startup

{

    public void Configuration(IAppBuilder app)

    {

        app.MapSignalR<MyConnection1>("/echo");

    }

}

3.前台js交互

引入相关js文件，在JavaScript.js中进行编程，与后台signalr服务端交互。

<!DOCTYPE html>

<html xmlns="http://www.w3.org/1999/xhtml">

<head>

    <meta http-equiv="Content-Type" content="text/html; charset=utf-8" />

    <script src="https://img.hcharts.cn/jquery/jquery-1.8.3.min.js"></script>

    <script src="https://img.hcharts.cn/highstock/highstock.js"></script>

    <script src="https://img.hcharts.cn/highcharts/modules/exporting.js"></script>

    <script src="https://img.hcharts.cn/highcharts-plugins/highcharts-zh_CN.js"></script>

    <script src="https://img.hcharts.cn/highcharts/themes/grid-light.js"></script>

    <script src="Scripts/moment.js"></script>

    <title>

        Signalr Test

    </title>

</head>

<body>

    <script src="Scripts/jquery-1.6.4.js"></script>

    <script src="Scripts/jquery.signalR-2.3.0.js"></script>

    <div id="main" style="width: 1500px;height:400px;"></div>

    <script src="JavaScript.js"></script>

</body>

</html>

4.编写交互js和后台调度数据

$.connection('/echo')与signalr服务端进行连接，$.receive()接收来自服务端推送。我的思路是当后台接收数据变化时，推送消息给客户端，当$.receive()接收到信息时，直接执行getdata()，刷新数据。

Highcharts.setOptions({

    global: {

        useUTC: true

    }

});

var chart = null;

var names = [];

var getTime8h = new Date('2015-01-01 08:00:00').getTime() - new Date('2015-01-01 00:00:00').getTime();

// Create the chart

$(document).ready(function () {

    seriesOptions = [];

    chart = new Highcharts.stockChart({

        chart: {

            renderTo: 'main',

            type: 'spline',

        },

        rangeSelector: {

            buttons: [{

                type: 'minute',

                count: 5,

                text: '5分钟',

            },

                {

                    type: 'hour',

                    count: 1,

                    text: '小时'

                }, {

                    type: 'day',

                    count: 1,

                    text: '一天'

                }, {

                    type: 'all',

                    text: '所有'

                }],

            inputEnabled: false,

            selected: 0,

        },

        //navigator: {

        //    adaptToUpdatedData: false,

        //    series: {

        //        data: datatim

        //    }

        //},

        title: {

            text: '曲线分析平台测试'

        },

        tooltip: {

            split: false,

            dateTimeLabelFormats: {

                millisecond: '%Y-%m-%d<br/> %H:%M:%S',

                second: '%Y-%m-%d<br/> %H:%M:%S',

                minute: '%Y-%m-%d<br/> %H:%M',

                hour: '%Y-%m-%d<br/> %H:%M',

                day: '%Y<br/> %m-%d',

                week: '%Y<br/> %m-%d',

                month: '%Y-%m',

                year: '%Y'

            },

        },

        exporting: {

            enabled: true,

        },

        //xAxis: {

        //    type: 'datetimee',

        //    data: time,

        //    tickPixelInterval: 150,

        //    maxZoom: 20 * 1000

        //}

        xAxis: {

            dateTimeLabelFormats: {

                millisecond: '%Y-%m-%d<br/> %H:%M:%S',

                second: '%Y-%m-%d<br/> %H:%M:%S',

                minute: '%Y-%m-%d<br/> %H:%M',

                hour: '%Y-%m-%d<br/> %H:%M',

                day: '%Y<br/> %m-%d',

                week: '%Y<br/> %m-%d',

                month: '%Y-%m',

                year: '%Y'

            },

        },

        yAxis: {

            minPadding: 0.2,

            maxPadding: 0.2,

            title: {

                text: 'sgrade',

                margin: 80

            }

        },

        series: [{

            name: 'demo',

            data: [],

        }]

    });

    var conn = $.connection('/echo');

    conn.start().done(function (data) {

        console.log("当前clientID=" + data.id);

    });

    //接受服务器的推送

    conn.received(function (data) {

        getdata();

        console.log("server返回的数据： " + data);

    });

    function getdata() {

        var datatim = [];

        var time = [];

        $.ajax({

            type: "post",

            async: false,            //异步请求（同步请求将会锁住浏览器，用户其他操作必须等待请求完成才可以执行）

            url: "Default.aspx?method=getdata",

            data: {},

            dataType: "json",        //返回数据形式为json

            success: function (data) {

                data.forEach(function (e, j) {

                    var a = new Array();

                   // console.log(e.datetimee);

                    a.push(Date.parse(e.datetimee) + getTime8h);

                    a.push(e.Sgrade);

                    datatim.push(a);

                });

                console.log(datatim);

                chart.series[0].setData(datatim);

            },

        })

    }

})

5.编写后台数据获取不需要改变（参照C#曲线分析平台的制作（三，三层构架+echarts显示））

Default.aspx后台编写

using BLL;

using Newtonsoft.Json;

using System;

using System.Collections.Generic;

using System.Data;

using System.Linq;

using System.Web;

using System.Web.UI;

using System.Web.UI.WebControls;

using DAL;

using System.Data.SqlClient;

using System.Configuration;

using Microsoft.AspNet.SignalR.Client;

using Microsoft.AspNet.SignalR;

public partial class _Default : System.Web.UI.Page

{

    protected void Page_Load(object sender, EventArgs e)

    {

        string method = Request.QueryString["method"];

        if (!string.IsNullOrEmpty(method))

        {

            if (method == "getdata")

            {

                    data();

            }

        }

    }

    public void data()

    {

        DataTable dt = new DataTable();

        dt = UserManage.returntable();

        // lists = new List<object>();

        //  lists = UserManage.returnlist();

        object JSONObj = (Object)JsonConvert.SerializeObject(dt);

        Response.Write(JSONObj);

        //  一定要加，不然前端接收失败

        Response.End();

    }

}

3.windows服务编写监控sqldependency变化：

先前考虑的是直接使用console后台监控，但考虑到其容易被人误操作给直接关闭，故而寻求更稳定的windows服务。

新建windows服务->编写services.cs文件：

改写网友提供的博客，然后在sqldependency触发变化事件时，添加相关signalr连接和数据发送（以用来触发前端客户端触发getdata())

var connection = new Connection("http://localhost:4454/echo");

connection.Start().Wait();

connection.Send("hello").Wait();

using Microsoft.AspNet.SignalR.Client;

using System;

using System.Collections.Generic;

using System.ComponentModel;

using System.Data;

using System.Data.SqlClient;

using System.Diagnostics;

using System.IO;

using System.Linq;

using System.ServiceProcess;

using System.Text;

using System.Threading.Tasks;

namespace WindowsService1

{

    public partial class Service1 : ServiceBase

    {

        string _connStr = @"Server=.;Database=SanCengDemo;Trusted_Connection=True";

        public Service1()

        {

            InitializeComponent();

        }

        protected override void OnStart(string[] args)

        {

            SqlDependency.Start(_connStr);//传入连接字符串,启动基于数据库的监听

            UpdateGrid();

        }

        private void UpdateGrid()

        {

            string _connStr = @"Server=.;Database=SanCengDemo;Trusted_Connection=True";

            using (SqlConnection connection = new SqlConnection(_connStr))

            {

                //依赖是基于某一张表的,而且查询语句只能是简单查询语句,不能带top或*,同时必须指定所有者,即类似[dbo].[]，如果where条件存在datetime类型，就会导致一直触发onChange事件

                using (SqlCommand command = new SqlCommand("select Sid,Sgrade,[DateTimee] From [dbo].[Student]", connection))

                {

                    command.CommandType = CommandType.Text;

                    connection.Open();

                    SqlDependency dependency = new SqlDependency(command);

                    dependency.OnChange += new OnChangeEventHandler(dependency_OnChange);

                    SqlDataReader sdr = command.ExecuteReader();

                    Console.WriteLine();

                    while (sdr.Read())

                    {

                        Console.WriteLine("Sid:{0}\tSgrade:{1}\tDateTimee:{2}", sdr["Sid"].ToString(), sdr["Sgrade"].ToString(),

 sdr["DateTimee"].ToString());

                    }

                    sdr.Close();

                }

            }

        }

        private void dependency_OnChange(object sender, SqlNotificationEventArgs e)

        {

            SqlDependency dependency = sender as SqlDependency;

            dependency.OnChange -= dependency_OnChange;

            if (e.Info != SqlNotificationInfo.Invalid)

            {

                var connection = new Connection("http://localhost:4454/echo");

                connection.Start().Wait();

                connection.Send("hello").Wait();

                UpdateGrid();//此处需重复注册<span style="font-family: Arial, Helvetica, sans-serif;">SqlDependency，每次注册只执行一次，SqlDependency.id可用用于验证注册唯一 编号

            }

        }

        protected override void OnStop()

        {

           // this.timer1.Enabled = false;

        }

    }

}

4.实验结果：

初步达到实验目的，下一步测试稳定性和占用的内存和CPU损耗情况。