基於C#的PISDK研究(代碼)

時間 2019-11-19

標籤基於 c# pisdk 研究代碼欄目 C# 简体版

原文原文鏈接

本篇文章主要利用PISDK從PI服務器取數，介紹多種取數方法。git

首先須要一些基礎的代碼，好比獲取PI服務的：小程序

        /// <summary>
        /// 獲取PI服務/// </summary>
        /// <param name="servername">//UID=PIUser;PWD=PIUserPassWord
        </param>
        /// <returns></returns>
        private Server GetServer(string servername)
        {
            try
            {
                if (!string.IsNullOrEmpty(servername))
                {
                    //採用認證方式登陸
                    server = pi.Servers[servername];
                    server.Open(connStr);
                }
                else
                {
                    //採用默認方式登陸
                    server = pi.Servers.DefaultServer;
                    server.Open();
                }

                if (server.Connected)
                {
                    return server;
                }
                else
                {
                    return null;
                }
            }
            catch (Exception ex)
            {
                MessageBox.Show(ex.Message);
                return null;
            }
        }

還有到PI服務器中找點的方法：c#

        /// <summary>
        /// 搜索PI中對應的數據點
        /// </summary>
        /// <param name="server">PI服務對象</param>
        /// <param name="condition">選擇tag的條件</param>
        /// <returns></returns>
        private PointList SearchPIPoints(Server server, String condition)
        {
              return server.GetPoints(condition);
        }

下面介紹取數方法：服務器

1. 取得單個tag快照值orm

        /// <summary>
        /// 取得單個tag快照值
        /// </summary>
        /// <param name="server">PI服務對象</param>
        /// <param name="tag">tag名稱</param>
        /// <returns></returns>
        private string GetSingleSnap(Server server, string tag)
        {
            string output=string.Empty;
            PIPoints piPoints = server.PIPoints;
            //採用標籤名稱的方式取得對象
            PIPoint piPoint = piPoints[tag];
            //調用方法取得快照值
            PIValue piValue = piPoint.Data.Snapshot;
            //取到該快照值時PI服務器時間
            PITimeServer.PITime piTime = piValue.TimeStamp;
            output = piTime.LocalDate.ToString() + " " + piValue.Value + Environment.NewLine;
            return output;
        }

2. 取得單個tag一段時間內的歷史值server

        /// <summary>
        /// 取得單個tag段時間內的歷史值
        /// </summary>
        /// <param name="server">PI服務對象</param>
        /// <param name="tag">tag名稱</param>
        /// <returns></returns>
        private string GetSingleHistory(Server server, string tag)
        {
            string output = string.Empty;
            PIPoints piPoints = server.PIPoints;
            PIPoint piPoint = piPoints[tag];
            //取得分鐘前到當前時間的歷史值
            PIValues piValues = piPoint.Data.RecordedValues(DateTime.Now.AddMinutes(-5).ToString(),
                DateTime.Now.ToString());
            foreach (PIValue piValue in piValues)
            {
                PITimeServer.PITime piTime = piValue.TimeStamp; //PI時間
                output += piTime.LocalDate.ToString() + " " + piValue.Value + Environment.NewLine;
            }
            return output;
        }

3. 取得多個tag快照值對象

        /// <summary>
        /// 取得多個tag取快照值
        /// </summary>
        /// <param name="server">PI服務對象</param>
        /// <param name="tag">tag值(tag='' or tag='')</param>
        /// <returns></returns>
        private string MultipleSnap(Server server, string tag)
        {
            string output = string.Empty;
            //取tag
            PointList ptlist = SearchPIPoints(server, tag);
            PISDKCommon.NamedValues nvErrs = new PISDKCommon.NamedValues();
            PointValues ptvalues = ptlist.Data.get_Snapshot(out nvErrs);

            foreach (PointValue myValue in ptvalues)
            {
                PITimeServer.PITime piTime = myValue.PIValue.TimeStamp; //PI時間
                if (myValue.PIValue.Value.GetType().IsCOMObject)
                {
                    //狀態值
                    DigitalState myDigState = (DigitalState)myValue.PIValue.Value;
                    output += myValue.PIPoint.Name + " " + piTime.LocalDate.ToString() + " " + myDigState.Name + Environment.NewLine;
                }
                else
                {
                    //模擬值
                    output += myValue.PIPoint.Name + " " + piTime.LocalDate.ToString() + " " + Convert.ToString(Math.Round(double.Parse(Convert.ToString(myValue.PIValue.Value)), 2)) + Environment.NewLine;
                }
            }
            return output;
        }

4. 取得多個tag一段歷史時間全部值blog

        /// <summary>
        /// 取得多個tag段歷史時間全部值
        /// </summary>
        /// <param name="server">PI服務對象</param>
        /// <param name="tag">tag名稱</param>
        /// <returns></returns>
        private string MultipleHistory1(Server server,string tag)
        {
            string output = string.Empty;
            PointList ptlist = SearchPIPoints(server, tag);
            string outPut = string.Empty;

            PISDKCommon.NamedValues nvErrs = new PISDKCommon.NamedValues();

            foreach (PIPoint piPoint in ptlist)
            {
                //獲取5分鐘前到當前時間的歷史值
                PIValues piValues = piPoint.Data.RecordedValues(DateTime.Now.AddMinutes(-5).ToString(),
                DateTime.Now.ToString());

                foreach (PIValue piValue in piValues)
                {
                    PITimeServer.PITime piTime = piValue.TimeStamp; //PI時間
                    output+= piPoint.Name + " " + piTime.LocalDate.ToString() + " " + piValue.Value + Environment.NewLine;
                }
            }
            return output;
        }

5. 取得多個tag歷史時刻值接口

        /// <summary>
        /// 取得多個tag段歷史時間點值
        /// </summary>
        /// <param name="server">PI服務對象</param>
        /// <param name="tag">tag名稱</param>
        /// <returns></returns>
        private string MultipleHistory2(Server server, string tag)
        {
            string output = string.Empty;
            PointList ptlist = SearchPIPoints(server, tag);
            
            PISDKCommon.NamedValues nvErrs = new PISDKCommon.NamedValues();

            PITimeServer.PITimeFormat piTime1 = new PITimeServer.PITimeFormat();
            piTime1.InputString = "*-2h";//or "2012-2-2 2:2:2"
            //獲取兩小時前的時刻值
            PointValues ptvalues = ptlist.Data.ArcValue(piTime1, RetrievalTypeConstants.rtAuto, out nvErrs);
            foreach (PointValue myValue in ptvalues)
            {
                PITimeServer.PITime piTime = myValue.PIValue.TimeStamp; //PI時間
                if (myValue.PIValue.Value.GetType().IsCOMObject)
                {
                    //狀態值
                    DigitalState myDigState = (DigitalState)myValue.PIValue.Value;
                    output+= myValue.PIPoint.Name + " " + piTime.LocalDate.ToString() + " " + myDigState.Name + Environment.NewLine;
                    
                }
                else
                {
                    //模擬值
                    output+= myValue.PIPoint.Name + " " + piTime.LocalDate.ToString() + " " + Convert.ToString(Math.Round(double.Parse(Convert.ToString(myValue.PIValue.Value)), 2)) + Environment.NewLine;

                }
            }
            return output;
        }

以上主要介紹瞭如何去從PI服務器獲取值，包括了獲取單個tag和多個tag，也包括了獲取快照值和歷史值，也許從效率上來看並非最優的，由於PI服務器版本限制，致使一些新的接口不能使用，若是您對效率有嚴格的要求，推薦您使用最新版本。ip

根據上述的方法，咱們也能夠製做一個小程序，界面以下：