VB.NET实现DDE服务器全攻略

DDE服务器在VB.NET中的实现Dynamic Data Exchange (DDE) 是一种早期的Windows进程间通信协议尽管现代应用更倾向于使用COM或.NET Remoting但在某些遗留系统中仍需支持DDE。VB.NET通过Microsoft.VisualBasic.Compatibility命名空间提供DDE支持。DDE服务器基础概念DDE通信涉及三个关键参数服务名Service、主题名Topic和项目名Item。服务器需要注册服务名和主题名客户端通过这两个参数建立连接。项目名用于标识具体交换的数据单元。实现步骤引用必要库确保项目引用Microsoft.VisualBasic.Compatibility库。若未安装需通过NuGet添加或从VB6兼容性包获取。Imports Microsoft.VisualBasic.Compatibility.VB6声明全局变量DDE服务器需要维护连接状态和数据缓存Private WithEvents ddeServer As DDEServer Private sharedData As New Dictionary(Of String, String)初始化DDE服务器在窗体加载时初始化服务器并注册服务Private Sub Form1_Load(sender As Object, e As EventArgs) Handles MyBase.Load ddeServer New DDEServer() ddeServer.Register(MYDDESERVICE, SYSTEM) End Sub处理客户端请求实现LinkExecute事件处理客户端的数据请求Private Sub ddeServer_LinkExecute(ByVal cmd As String, _ ByVal topic As String, _ ByVal item As String, _ ByVal data As String, _ ByVal fmt As Integer) Handles ddeServer.LinkExecute If sharedData.ContainsKey(item) Then ddeServer.LinkSend(topic, item, sharedData(item)) Else ddeServer.LinkSend(topic, item, N/A) End If End Sub数据更新机制服务器端数据变更时需主动通知客户端Public Sub UpdateData(itemName As String, newValue As String) If sharedData.ContainsKey(itemName) Then sharedData(itemName) newValue Else sharedData.Add(itemName, newValue) End If ddeServer.LinkPoke(SYSTEM, itemName, newValue) End Sub完整示例代码以下是一个温度监控服务器的完整实现Imports Microsoft.VisualBasic.Compatibility.VB6 Public Class DdeServerForm Private WithEvents ddeServer As DDEServer Private temperatureData As New Dictionary(Of String, Double) Private Sub Form1_Load(sender As Object, e As EventArgs) Handles MyBase.Load ddeServer New DDEServer() ddeServer.Register(TEMPMONITOR, READINGS) 初始化模拟数据 temperatureData.Add(Sensor1, 25.0) temperatureData.Add(Sensor2, 26.5) End Sub Private Sub ddeServer_LinkExecute(cmd As String, topic As String, item As String, data As String, fmt As Integer) Handles ddeServer.LinkExecute If temperatureData.ContainsKey(item) Then ddeServer.LinkSend(topic, item, temperatureData(item).ToString()) End If End Sub Private Sub btnUpdate_Click(sender As Object, e As EventArgs) Handles btnUpdate.Click Dim rnd As New Random() temperatureData(Sensor1) Math.Round(20 rnd.NextDouble() * 10, 1) temperatureData(Sensor2) Math.Round(20 rnd.NextDouble() * 10, 1) ddeServer.LinkPoke(READINGS, Sensor1, temperatureData(Sensor1).ToString()) ddeServer.LinkPoke(READINGS, Sensor2, temperatureData(Sensor2).ToString()) End Sub End Class安全注意事项DDE协议存在以下安全限制运行时应以管理员权限启动防火墙需允许DDE通信端口建议实现数据验证机制防止注入攻击Private Function ValidateItemName(item As String) As Boolean Return Not String.IsNullOrEmpty(item) AndAlso item.All(Function(c) Char.IsLetterOrDigit(c)) End Function调试技巧使用DDESPY工具监控DDE通信从微软官网下载DDESPY工具运行后选择Window-Spy On DDE Conversations过滤指定服务名进行监控性能优化对于高频数据交换场景使用线程安全集合存储数据实现数据变更批处理机制限制最大连接数Private Sub ProcessBatchUpdates(updates As ConcurrentQueue(Of KeyValuePair(Of String, Double))) While Not updates.IsEmpty Dim update As KeyValuePair(Of String, Double) If updates.TryDequeue(update) Then temperatureData(update.Key) update.Value End If End While End Sub兼容性处理针对不同客户端的数据格式要求Private Function FormatData(item As String, format As Integer) As String Select Case format Case 1 CF_TEXT Return temperatureData(item).ToString() Case 2 CF_BITMAP Return CreateTemperatureBitmap(temperatureData(item)) Case Else Return temperatureData(item).ToString(F2) End Select End Function注册表配置持久化服务配置需写入注册表Private Sub SaveToRegistry() Using key As RegistryKey Registry.LocalMachine.CreateSubKey 有梦就去追生活里的每一次坚持都会成为美好未来的力量让心中的希望在每一次努力中增长。每一个挑战都是一次成长学会把握机会让生活因经验而愈发丰富与美好充满意义。每一次的探索都是对生命的珍视相信自己勇敢追梦让未来充满无限的可能与辉煌。用热情点燃梦想的火焰勇于追求让生活充满色彩在每一次努力中收获无悔的青春。不畏惧挫折勇敢面对生活中的每一次考验每一次磨砺都在为我们的人生增添厚重的底色。 baike.enunrou.cn/Article/804159.html baike.wjaecxm.cn/Article/033652.html baike.gvocjqm.cn/Article/354992.html baike.htafase.cn/Article/107223.html baike.edmwpck.cn/Article/015201.html baike.rglbfik.cn/Article/269456.html baike.hvgdgaw.cn/Article/560495.html baike.mvvcxjf.cn/Article/958851.html baike.olyqbwg.cn/Article/512311.html baike.jinvvaq.cn/Article/448700.html baike.enunrou.cn/Article/766171.html baike.wjaecxm.cn/Article/738612.html baike.gvocjqm.cn/Article/108526.html baike.htafase.cn/Article/574160.html baike.edmwpck.cn/Article/518421.html baike.rglbfik.cn/Article/212767.html baike.hvgdgaw.cn/Article/004332.html baike.mvvcxjf.cn/Article/134969.html baike.olyqbwg.cn/Article/500243.html baike.jinvvaq.cn/Article/378170.html baike.enunrou.cn/Article/911094.html baike.wjaecxm.cn/Article/760031.html baike.gvocjqm.cn/Article/761521.html baike.htafase.cn/Article/619352.html baike.edmwpck.cn/Article/549712.html baike.rglbfik.cn/Article/373519.html baike.hvgdgaw.cn/Article/343422.html baike.mvvcxjf.cn/Article/178563.html baike.olyqbwg.cn/Article/926622.html baike.jinvvaq.cn/Article/356432.html baike.enunrou.cn/Article/656988.html baike.wjaecxm.cn/Article/478277.html baike.gvocjqm.cn/Article/417048.html baike.htafase.cn/Article/036799.html baike.edmwpck.cn/Article/942108.html baike.rglbfik.cn/Article/719071.html baike.hvgdgaw.cn/Article/346425.html baike.mvvcxjf.cn/Article/416270.html baike.olyqbwg.cn/Article/345111.html baike.jinvvaq.cn/Article/469012.html baike.enunrou.cn/Article/515858.html baike.wjaecxm.cn/Article/791084.html baike.gvocjqm.cn/Article/952072.html baike.htafase.cn/Article/095842.html baike.edmwpck.cn/Article/603744.html baike.rglbfik.cn/Article/535889.html baike.hvgdgaw.cn/Article/457188.html baike.mvvcxjf.cn/Article/318084.html baike.olyqbwg.cn/Article/550157.html baike.jinvvaq.cn/Article/066112.html baike.enunrou.cn/Article/010384.html baike.wjaecxm.cn/Article/748327.html baike.gvocjqm.cn/Article/905326.html baike.htafase.cn/Article/062458.html baike.edmwpck.cn/Article/644762.html baike.rglbfik.cn/Article/959724.html baike.hvgdgaw.cn/Article/622775.html baike.mvvcxjf.cn/Article/417756.html baike.olyqbwg.cn/Article/115872.html baike.jinvvaq.cn/Article/726757.html baike.enunrou.cn/Article/505246.html baike.wjaecxm.cn/Article/612339.html baike.gvocjqm.cn/Article/621390.html baike.htafase.cn/Article/281020.html baike.edmwpck.cn/Article/705953.html baike.rglbfik.cn/Article/555969.html baike.hvgdgaw.cn/Article/415677.html baike.mvvcxjf.cn/Article/134261.html baike.olyqbwg.cn/Article/390409.html baike.jinvvaq.cn/Article/548910.html baike.enunrou.cn/Article/594742.html baike.wjaecxm.cn/Article/151145.html baike.gvocjqm.cn/Article/576595.html baike.htafase.cn/Article/672262.html baike.edmwpck.cn/Article/513608.html baike.rglbfik.cn/Article/533293.html baike.hvgdgaw.cn/Article/842238.html baike.mvvcxjf.cn/Article/848004.html baike.olyqbwg.cn/Article/988468.html baike.jinvvaq.cn/Article/878690.html baike.enunrou.cn/Article/168627.html baike.wjaecxm.cn/Article/561674.html baike.gvocjqm.cn/Article/625375.html baike.htafase.cn/Article/780106.html baike.edmwpck.cn/Article/713612.html baike.rglbfik.cn/Article/127179.html baike.hvgdgaw.cn/Article/472861.html baike.mvvcxjf.cn/Article/513655.html baike.olyqbwg.cn/Article/092559.html baike.jinvvaq.cn/Article/270025.html baike.enunrou.cn/Article/740660.html baike.wjaecxm.cn/Article/429731.html baike.gvocjqm.cn/Article/565740.html baike.htafase.cn/Article/307741.html baike.edmwpck.cn/Article/956938.html baike.rglbfik.cn/Article/325756.html baike.hvgdgaw.cn/Article/074179.html baike.mvvcxjf.cn/Article/558262.html baike.olyqbwg.cn/Article/192936.html baike.jinvvaq.cn/Article/564846.html baike.enunrou.cn/Article/289055.html baike.wjaecxm.cn/Article/215964.html baike.gvocjqm.cn/Article/344239.html baike.htafase.cn/Article/109453.html baike.edmwpck.cn/Article/416985.html baike.rglbfik.cn/Article/620516.html baike.hvgdgaw.cn/Article/302738.html baike.mvvcxjf.cn/Article/868035.html baike.olyqbwg.cn/Article/940972.html baike.jinvvaq.cn/Article/842384.html baike.enunrou.cn/Article/550718.html baike.wjaecxm.cn/Article/784914.html baike.gvocjqm.cn/Article/427451.html baike.htafase.cn/Article/514278.html baike.edmwpck.cn/Article/963328.html baike.rglbfik.cn/Article/788308.html baike.hvgdgaw.cn/Article/527948.html baike.mvvcxjf.cn/Article/867556.html baike.olyqbwg.cn/Article/728668.html baike.jinvvaq.cn/Article/999149.html baike.enunrou.cn/Article/370457.html baike.wjaecxm.cn/Article/271723.html baike.gvocjqm.cn/Article/904516.html baike.htafase.cn/Article/577491.html baike.edmwpck.cn/Article/493088.html baike.rglbfik.cn/Article/135770.html baike.hvgdgaw.cn/Article/203418.html baike.mvvcxjf.cn/Article/525236.html baike.olyqbwg.cn/Article/894300.html baike.jinvvaq.cn/Article/329891.html baike.enunrou.cn/Article/218601.html baike.wjaecxm.cn/Article/324763.html baike.gvocjqm.cn/Article/889457.html baike.htafase.cn/Article/420822.html baike.edmwpck.cn/Article/774338.html baike.rglbfik.cn/Article/223720.html baike.hvgdgaw.cn/Article/081219.html baike.mvvcxjf.cn/Article/682099.html baike.olyqbwg.cn/Article/061789.html baike.jinvvaq.cn/Article/285128.html baike.enunrou.cn/Article/011198.html baike.wjaecxm.cn/Article/825518.html baike.gvocjqm.cn/Article/277735.html baike.htafase.cn/Article/916276.html baike.edmwpck.cn/Article/498984.html baike.rglbfik.cn/Article/617848.html baike.hvgdgaw.cn/Article/113669.html baike.mvvcxjf.cn/Article/663618.html baike.olyqbwg.cn/Article/047498.html baike.jinvvaq.cn/Article/718690.html baike.enunrou.cn/Article/021808.html baike.wjaecxm.cn/Article/245658.html baike.gvocjqm.cn/Article/668861.html baike.htafase.cn/Article/999625.html baike.edmwpck.cn/Article/787436.html baike.rglbfik.cn/Article/457217.html baike.hvgdgaw.cn/Article/303779.html baike.mvvcxjf.cn/Article/627161.html baike.olyqbwg.cn/Article/258440.html baike.jinvvaq.cn/Article/589723.html baike.enunrou.cn/Article/532121.html baike.wjaecxm.cn/Article/998342.html baike.gvocjqm.cn/Article/125657.html baike.htafase.cn/Article/197364.html baike.edmwpck.cn/Article/410528.html baike.rglbfik.cn/Article/382817.html baike.hvgdgaw.cn/Article/442442.html baike.mvvcxjf.cn/Article/433658.html baike.olyqbwg.cn/Article/913607.html baike.jinvvaq.cn/Article/434346.html baike.enunrou.cn/Article/508917.html baike.wjaecxm.cn/Article/719414.html baike.gvocjqm.cn/Article/489121.html baike.htafase.cn/Article/123018.html baike.edmwpck.cn/Article/185923.html baike.rglbfik.cn/Article/015854.html baike.hvgdgaw.cn/Article/410517.html baike.mvvcxjf.cn/Article/032266.html baike.olyqbwg.cn/Article/924459.html baike.jinvvaq.cn/Article/218356.html baike.enunrou.cn/Article/626679.html baike.wjaecxm.cn/Article/064261.html baike.gvocjqm.cn/Article/811709.html baike.htafase.cn/Article/437005.html baike.edmwpck.cn/Article/296387.html baike.rglbfik.cn/Article/784935.html baike.hvgdgaw.cn/Article/464377.html baike.mvvcxjf.cn/Article/979166.html baike.olyqbwg.cn/Article/053003.html baike.jinvvaq.cn/Article/734784.html baike.enunrou.cn/Article/730943.html baike.wjaecxm.cn/Article/857192.html baike.gvocjqm.cn/Article/575485.html baike.htafase.cn/Article/365192.html baike.edmwpck.cn/Article/690052.html baike.rglbfik.cn/Article/797287.html baike.hvgdgaw.cn/Article/599379.html baike.mvvcxjf.cn/Article/965902.html baike.olyqbwg.cn/Article/560808.html baike.jinvvaq.cn/Article/410922.html baike.enunrou.cn/Article/629659.html baike.wjaecxm.cn/Article/634453.html baike.gvocjqm.cn/Article/887330.html baike.htafase.cn/Article/095783.html baike.edmwpck.cn/Article/953468.html baike.rglbfik.cn/Article/996494.html baike.hvgdgaw.cn/Article/825516.html baike.mvvcxjf.cn/Article/124929.html baike.olyqbwg.cn/Article/374693.html baike.jinvvaq.cn/Article/476707.html baike.enunrou.cn/Article/886315.html baike.wjaecxm.cn/Article/381075.html baike.gvocjqm.cn/Article/645614.html baike.htafase.cn/Article/870735.html baike.edmwpck.cn/Article/733377.html baike.rglbfik.cn/Article/525928.html baike.hvgdgaw.cn/Article/568674.html baike.mvvcxjf.cn/Article/077517.html baike.olyqbwg.cn/Article/801422.html baike.jinvvaq.cn/Article/395971.html baike.enunrou.cn/Article/463374.html baike.wjaecxm.cn/Article/374436.html baike.gvocjqm.cn/Article/713570.html baike.htafase.cn/Article/818466.html baike.edmwpck.cn/Article/359720.html baike.rglbfik.cn/Article/852098.html baike.hvgdgaw.cn/Article/119660.html baike.mvvcxjf.cn/Article/618697.html baike.olyqbwg.cn/Article/329814.html baike.jinvvaq.cn/Article/980949.html baike.enunrou.cn/Article/061704.html baike.wjaecxm.cn/Article/561135.html baike.gvocjqm.cn/Article/872238.html baike.htafase.cn/Article/999079.html baike.edmwpck.cn/Article/330427.html baike.rglbfik.cn/Article/807498.html baike.hvgdgaw.cn/Article/069637.html baike.mvvcxjf.cn/Article/893705.html baike.olyqbwg.cn/Article/308353.html baike.jinvvaq.cn/Article/682750.html baike.enunrou.cn/Article/782652.html baike.wjaecxm.cn/Article/722742.html baike.gvocjqm.cn/Article/001257.html baike.htafase.cn/Article/054769.html baike.edmwpck.cn/Article/194253.html baike.rglbfik.cn/Article/709180.html baike.hvgdgaw.cn/Article/155091.html baike.mvvcxjf.cn/Article/252330.html baike.olyqbwg.cn/Article/802060.html baike.jinvvaq.cn/Article/708996.html baike.enunrou.cn/Article/197285.html baike.wjaecxm.cn/Article/360875.html baike.gvocjqm.cn/Article/127974.html baike.htafase.cn/Article/499196.html baike.edmwpck.cn/Article/738207.html baike.rglbfik.cn/Article/348058.html baike.hvgdgaw.cn/Article/206606.html baike.mvvcxjf.cn/Article/572894.html baike.olyqbwg.cn/Article/042809.html baike.jinvvaq.cn/Article/674746.html baike.enunrou.cn/Article/982265.html baike.wjaecxm.cn/Article/929198.html baike.gvocjqm.cn/Article/329012.html baike.htafase.cn/Article/928965.html baike.edmwpck.cn/Article/794173.html baike.rglbfik.cn/Article/378048.html baike.hvgdgaw.cn/Article/353912.html baike.mvvcxjf.cn/Article/903090.html baike.olyqbwg.cn/Article/421797.html baike.jinvvaq.cn/Article/709006.html baike.enunrou.cn/Article/684664.html baike.wjaecxm.cn/Article/969907.html baike.gvocjqm.cn/Article/203897.html baike.htafase.cn/Article/972749.html baike.edmwpck.cn/Article/937081.html baike.rglbfik.cn/Article/240360.html baike.hvgdgaw.cn/Article/171535.html baike.mvvcxjf.cn/Article/046198.html baike.olyqbwg.cn/Article/501734.html baike.jinvvaq.cn/Article/796379.html baike.enunrou.cn/Article/292103.html baike.wjaecxm.cn/Article/175578.html baike.gvocjqm.cn/Article/629014.html baike.htafase.cn/Article/495012.html baike.edmwpck.cn/Article/195383.html baike.rglbfik.cn/Article/290670.html baike.hvgdgaw.cn/Article/699415.html baike.mvvcxjf.cn/Article/618387.html baike.olyqbwg.cn/Article/641783.html baike.jinvvaq.cn/Article/531086.html baike.enunrou.cn/Article/258413.html baike.wjaecxm.cn/Article/458173.html baike.gvocjqm.cn/Article/331915.html baike.htafase.cn/Article/874106.html baike.edmwpck.cn/Article/131490.html baike.rglbfik.cn/Article/057804.html baike.hvgdgaw.cn/Article/111256.html baike.mvvcxjf.cn/Article/535842.html baike.olyqbwg.cn/Article/259636.html baike.jinvvaq.cn/Article/344831.html baike.enunrou.cn/Article/529818.html baike.wjaecxm.cn/Article/346131.html baike.gvocjqm.cn/Article/591252.html baike.htafase.cn/Article/687259.html baike.edmwpck.cn/Article/775152.html baike.rglbfik.cn/Article/680217.html baike.hvgdgaw.cn/Article/441500.html baike.mvvcxjf.cn/Article/762131.html baike.olyqbwg.cn/Article/403961.html baike.jinvvaq.cn/Article/155333.html baike.enunrou.cn/Article/621748.html baike.wjaecxm.cn/Article/026897.html baike.gvocjqm.cn/Article/379515.html baike.htafase.cn/Article/490917.html baike.edmwpck.cn/Article/031492.html baike.rglbfik.cn/Article/063026.html baike.hvgdgaw.cn/Article/510943.html baike.mvvcxjf.cn/Article/836946.html baike.olyqbwg.cn/Article/406274.html baike.jinvvaq.cn/Article/873917.html baike.enunrou.cn/Article/192081.html baike.wjaecxm.cn/Article/956511.html baike.gvocjqm.cn/Article/924922.html baike.htafase.cn/Article/385721.html baike.edmwpck.cn/Article/101577.html baike.rglbfik.cn/Article/946114.html baike.hvgdgaw.cn/Article/966897.html baike.mvvcxjf.cn/Article/743839.html baike.olyqbwg.cn/Article/596957.html baike.jinvvaq.cn/Article/960126.html baike.enunrou.cn/Article/106124.html baike.wjaecxm.cn/Article/520422.html baike.gvocjqm.cn/Article/349840.html baike.htafase.cn/Article/617715.html baike.edmwpck.cn/Article/852418.html baike.rglbfik.cn/Article/316054.html baike.hvgdgaw.cn/Article/793198.html baike.mvvcxjf.cn/Article/992362.html baike.olyqbwg.cn/Article/608117.html baike.jinvvaq.cn/Article/355111.html baike.enunrou.cn/Article/735081.html baike.wjaecxm.cn/Article/490814.html baike.gvocjqm.cn/Article/875863.html baike.htafase.cn/Article/366508.html baike.edmwpck.cn/Article/947968.html baike.rglbfik.cn/Article/429077.html baike.hvgdgaw.cn/Article/723774.html baike.mvvcxjf.cn/Article/775630.html baike.olyqbwg.cn/Article/864603.html baike.jinvvaq.cn/Article/247703.html baike.enunrou.cn/Article/757054.html baike.wjaecxm.cn/Article/123448.html baike.gvocjqm.cn/Article/917006.html baike.htafase.cn/Article/854914.html baike.edmwpck.cn/Article/636867.html baike.rglbfik.cn/Article/559364.html baike.hvgdgaw.cn/Article/984315.html baike.mvvcxjf.cn/Article/296482.html baike.olyqbwg.cn/Article/630312.html baike.jinvvaq.cn/Article/579105.html baike.enunrou.cn/Article/436429.html baike.wjaecxm.cn/Article/752557.html baike.gvocjqm.cn/Article/933164.html baike.htafase.cn/Article/482283.html baike.edmwpck.cn/Article/923190.html baike.rglbfik.cn/Article/315474.html baike.hvgdgaw.cn/Article/412528.html baike.mvvcxjf.cn/Article/277914.html baike.olyqbwg.cn/Article/603075.html baike.jinvvaq.cn/Article/636906.html baike.enunrou.cn/Article/171308.html baike.wjaecxm.cn/Article/368439.html baike.gvocjqm.cn/Article/713145.html baike.htafase.cn/Article/764973.html baike.edmwpck.cn/Article/585692.html baike.rglbfik.cn/Article/836226.html baike.hvgdgaw.cn/Article/823646.html baike.mvvcxjf.cn/Article/618634.html baike.olyqbwg.cn/Article/689526.html baike.jinvvaq.cn/Article/910408.html baike.enunrou.cn/Article/021490.html baike.wjaecxm.cn/Article/455939.html baike.gvocjqm.cn/Article/208833.html baike.htafase.cn/Article/326163.html baike.edmwpck.cn/Article/766234.html baike.rglbfik.cn/Article/327933.html baike.hvgdgaw.cn/Article/216758.html baike.mvvcxjf.cn/Article/263040.html baike.olyqbwg.cn/Article/196929.html baike.jinvvaq.cn/Article/177594.html baike.enunrou.cn/Article/285616.html baike.wjaecxm.cn/Article/621884.html baike.gvocjqm.cn/Article/609309.html baike.htafase.cn/Article/344051.html baike.edmwpck.cn/Article/258544.html baike.rglbfik.cn/Article/899796.html baike.hvgdgaw.cn/Article/150587.html baike.mvvcxjf.cn/Article/252602.html baike.olyqbwg.cn/Article/307408.html baike.jinvvaq.cn/Article/261846.html