SQL Server：UPDATE不使用C＃更新数据库
我有一个网页，上面有一个网页表格。 该表单预先填充了SQL Server数据库中的数据。 用户可以进入并编辑任何字段，然后单击底部的“保存”按钮更新数据库中的记录。 出于某种原因，当我预先填充数据时，更新语句不会更新数据库中的记录。 如果我在页面加载方法中删除预填充表单的代码，则update语句应该正常工作。 当我在页面加载方法中预填充数据的表单时，更新语句似乎是使用与其中已有的相同数据更新记录，而不是用户输入的新信息。 我完全迷失了如何解决这个问题，因为表单必须预先加载数据，以便用户可以分别编辑表单。
有人可以指出我需要做出的错误或纠正吗？ 我打了一个普通的砖墙:(
您将在下面找到页面加载方法和保存按钮单击事件处理程序。
protected void Page_Load(object sender, EventArgs e) { String projectID = Request.QueryString["jobID"]; String reportID = Request.QueryString["reportID"]; string selectStatement = "SELECT * FROM ahu_data WHERE unit_ID = " + reportID; string sqlConnectionString = "Removed for Security"; using (SqlConnection connection1 = new SqlConnection(sqlConnectionString)) { SqlCommand selectCommand = new SqlCommand(selectStatement, connection1); connection1.Open(); using (SqlDataReader reader = selectCommand.ExecuteReader()) { while (reader.Read()) { UMTextBox.Text = reader["make"].ToString(); UMOTextBox.Text = reader["model"].ToString(); UTTextBox.Text = reader["type"].ToString(); USITextBox.Text = reader["size"].ToString(); USTextBox.Text = reader["serial"].ToString(); UATextBox.Text = reader["arrangement"].ToString(); UCTextBox.Text = reader["class"].ToString(); UDTextBox.Text = reader["discharge"].ToString(); UMSTextBox.Text = reader["make_sheave"].ToString(); USDTextBox.Text = reader["sheave_diameter"].ToString(); USBTextBox.Text = reader["sheave_bore"].ToString(); UBNTextBox.Text = reader["belts"].ToString(); UBSTextBox.Text = reader["belt_size"].ToString(); UFNTextBox.Text = reader["filters"].ToString(); UFSTextBox.Text = reader["filter_size"].ToString(); TCFMDTextBox.Text = reader["unitTotalCFMDesign"].ToString(); TCFMATextBox.Text = reader["unitTotalCFMActual"].ToString(); RACFMDTextBox.Text = reader["unitReturnAirCFMDesign"].ToString(); RACFMATextBox.Text = reader["unitReturnAirCFMActual"].ToString(); OACFMDTextBox.Text = reader["unitOutsideAirCFMDesign"].ToString(); OACFMATextBox.Text = reader["unitOutsideAirCFMActual"].ToString(); EACFMDTextBox.Text = reader["unitExhaustAirCFMDesign"].ToString(); EACFMATextBox.Text = reader["unitExhaustAirCFMActual"].ToString(); FRPMDTextBox.Text = reader["unitFanRPMDesign"].ToString(); FRPMATextBox.Text = reader["unitFanRPMActual"].ToString(); MRPMDTextBox.Text = reader["unitMotorRPMDesign"].ToString(); MRPMATextBox.Text = reader["unitMotorRPMActual"].ToString(); MVDTextBox.Text = reader["unitMotorVoltsDesign"].ToString(); MVATextBox.Text = reader["unitMotorVoltsActual"].ToString(); MADTextBox.Text = reader["unitMotorAmpsDesign"].ToString(); MAATextBox.Text = reader["unitMotorAmpsActual"].ToString(); MMTextBox.Text = reader["motor_make"].ToString(); MFTextBox.Text = reader["motor_frame"].ToString(); MHPTextBox.Text = reader["motor_hp"].ToString(); MRPMTextBox.Text = reader["motor_rpm"].ToString(); MVTextBox.Text = reader["motor_volts"].ToString(); MPHTextBox.Text = reader["motor_phasehz"].ToString(); MFLATextBox.Text = reader["motor_fl_amps"].ToString(); MSFTextBox.Text = reader["motor_sf"].ToString(); MMSTextBox.Text = reader["motor_make_sheave"].ToString(); MSDTextBox.Text = reader["motor_sheave_diameter"].ToString(); MSBTextBox.Text = reader["motor_sheave_bore"].ToString(); MODTextBox.Text = reader["motor_operating_diameter"].ToString(); MSCDTextBox.Text = reader["motor_sheave_center_distance"].ToString(); TSPDTextBox.Text = reader["motorTotalSPDesign"].ToString(); TSPATextBox.Text = reader["motorTotalSPActual"].ToString(); ESPDTextBox.Text = reader["motorEnteringSPDesign"].ToString(); ESPATextBox.Text = reader["motorEnteringSPActual"].ToString(); SSPDTextBox.Text = reader["motorSuctionSPDesign"].ToString(); SSPATextBox.Text = reader["motorSuctionSPActual"].ToString(); DSPDTextBox.Text = reader["motorDischargeSPDesign"].ToString(); DSPATextBox.Text = reader["motorDischargeSPActual"].ToString(); PCSPDTextBox.Text = reader["motorPreheatCoilSPDesign"].ToString(); PCSPATextBox.Text = reader["motorPreheatCoilSPActual"].ToString(); CCSPDTextBox.Text = reader["motorCoolingCoilSPDesign"].ToString(); CCSPATextBox.Text = reader["motorCoolingCoilSPActual"].ToString(); RCSPDTextBox.Text = reader["motorReheatCoilSPDesign"].ToString(); RCSPATextBox.Text = reader["motorReheatCoilSPActual"].ToString(); FSPDTextBox.Text = reader["motorFilterSPDesign"].ToString(); FSPATextBox.Text = reader["motorFilterSPActual"].ToString(); AFSPDTextBox.Text = reader["motorAfterFilterSPDesign"].ToString(); AFSPATextBox.Text = reader["motorAfterFilterSPActual"].ToString(); WSPDTextBox.Text = reader["motorWheelSPDesign"].ToString(); WSPATextBox.Text = reader["motorWheelSPActual"].ToString(); RemarksTextArea.Text = reader["remarks"].ToString(); } } connection1.Close(); } } 这是保存按钮单击处理程序，用于更新数据库中的记录。
protected void SaveReportButton_Click(object sender, EventArgs e) { String projectID = Request.QueryString["jobID"]; String reportID = Request.QueryString["reportID"]; string unitMake = UMTextBox.Text; string unitModel = UMOTextBox.Text; string unitType = UTTextBox.Text; string unitSize = USITextBox.Text; string unitSerial = USTextBox.Text; string unitArrangement = UATextBox.Text; string unitClass = UCTextBox.Text; string unitDischarge = UDTextBox.Text; string unitMS = UMSTextBox.Text; string unitSD = USDTextBox.Text; string unitSB = USBTextBox.Text; string unitBeltNumber = UBNTextBox.Text; string unitBeltSize = UBSTextBox.Text; string unitFilterNumber = UFNTextBox.Text; string unitFilterSize = UFSTextBox.Text; string unitTotalCFMDesign = TCFMDTextBox.Text; string unitTotalCFMActual = TCFMATextBox.Text; string unitReturnAirCFMDesign = RACFMDTextBox.Text; string unitReturnAirCFMActual = RACFMATextBox.Text; string unitOutsideAirCFMDesign = OACFMDTextBox.Text; string unitOutsideAirCFMActual = OACFMATextBox.Text; string unitExhaustAirCFMDesign = EACFMDTextBox.Text; string unitExhaustAirCFMActual = EACFMATextBox.Text; string unitFanRPMDesign = FRPMDTextBox.Text; string unitFanRPMActual = FRPMATextBox.Text; string unitMotorRPMDesign = MRPMDTextBox.Text; string unitMotorRPMActual = MRPMATextBox.Text; string unitMotorVoltsDesign = MVDTextBox.Text; string unitMotorVoltsActual = MVATextBox.Text; string unitMotorAmpsDesign = MADTextBox.Text; string unitMotorAmpsActual = MAATextBox.Text; string motorMake = MMTextBox.Text; string motorFrame = MFTextBox.Text; string motorHP = MHPTextBox.Text; string motorRPM = MRPMTextBox.Text; string motorVolts = MVTextBox.Text; string motorPhaseHz = MPHTextBox.Text; string motorFullLoadAmps = MFLATextBox.Text; string motorSF = MSFTextBox.Text; string motorMakeSheave = MMSTextBox.Text; string motorSheaveDiameter = MSDTextBox.Text; string motorSheaveBore = MSBTextBox.Text; string motorOperatingDiameter = MODTextBox.Text; string motorSheaveCDistance = MSCDTextBox.Text; string motorTotalSPDesign = TSPDTextBox.Text; string motorTotalSPActual = TSPATextBox.Text; string motorEnteringSPDesign = ESPDTextBox.Text; string motorEnteringSPActual = ESPATextBox.Text; string motorSuctionSPDesign = SSPDTextBox.Text; string motorSuctionSPActual = SSPATextBox.Text; string motorDischargeSPDesign = DSPDTextBox.Text; string motorDischargeSPActual = DSPATextBox.Text; string motorPreheatCoilSPDesign = PCSPDTextBox.Text; string motorPreheatCoilSPActual = PCSPATextBox.Text; string motorCoolingCoilSPDesign = CCSPDTextBox.Text; string motorCoolingCoilSPActual = CCSPATextBox.Text; string motorReheatCoilSPDesign = RCSPDTextBox.Text; string motorReheatCoilSPActual = RCSPATextBox.Text; string motorFilterSPDesign = FSPDTextBox.Text; string motorFilterSPActual = FSPATextBox.Text; string motorAfterFilterSPDesign = AFSPDTextBox.Text; string motorAfterFilterSPActual = AFSPATextBox.Text; string motorWheelSPDesign = WSPDTextBox.Text; string motorWheelSPActual = WSPATextBox.Text; string remarks = RemarksTextArea.Text; string updateStatement = @"UPDATE ahu_data SET make=@UNITMAKE, model=@UNITMODEL, type=@UNITTYPE, size=@UNITSIZE, serial=@UNITSERIAL, arrangement=@UNITARRANGEMENT, class=@UNITCLASS, discharge=@UNITDISCHARGE, make_sheave=@UNITMS, sheave_diameter=@UNITSD, sheave_bore=@UNITSB, belts=@UNITBELTNUMBER, belt_size=@UNITBELTSIZE, filters=@UNITFILTERNUMBER, filter_size=@UNITBELTSIZE, unitTotalCFMDesign=@UNITTOTALCFMDESIGN, unitTotalCFMActual=@UNITTOTALCFMACTUAL, unitReturnAirCFMDesign=@UNITRETURNAIRCFMDESIGN, unitReturnAirCFMActual=@UNITRETURNAIRCFMACTUAL, unitOutsideAirCFMDesign=@UNITOUTSIDEAIRCFMDESIGN, unitOutsideAirCFMActual=@UNITOUTSIDEAIRCFMACTUAL, unitExhaustAirCFMDesign=@UNITEXHAUSTAIRCFMDESIGN, unitExhaustAirCFMActual=@UNITEXHAUSTAIRCFMACTUAL, unitFanRPMDesign=@UNITFANRPMDESIGN, unitFanRPMActual=@UNITFANRPMACTUAL, unitMotorRPMDesign=@UNITMOTORRPMDESIGN, unitMotorRPMActual=@UNITMOTORRPMACTUAL, unitMotorVoltsDesign=@UNITMOTORVOLTSDESIGN, unitMotorVoltsActual=@UNITMOTORVOLTSACTUAL, unitMotorAmpsDesign=@UNITMOTORAMPSDESIGN, unitMotorAmpsActual=@UNITMOTORAMPSACTUAL, motor_make=@MOTORMAKE, motor_frame=@MOTORFRAME, motor_hp=@MOTORHP, motor_rpm=@MOTORRPM, motor_volts=@MOTORVOLTS, motor_phasehz=@MOTORPHASEHZ, motor_fl_amps=@MOTORFULLLOADAMPS, motor_sf=@MOTORSF, motor_make_sheave=@MOTORMAKESHEAVE, motor_sheave_diameter=@MOTORSHEAVEDIAMETER, motor_sheave_bore=@MOTORSHEAVEBORE, motor_operating_diameter=@MOTOROPERATINGDIAMETER, motor_sheave_center_distance=@MOTORSHEAVECDISTANCE, motorTotalSPDesign=@MOTORTOTALSPDESIGN, motorTotalSPActual=@MOTORTOTALSPACTUAL, motorEnteringSPDesign=@MOTORENTERINGSPDESIGN, motorEnteringSPActual=@MOTORENTERINGSPACTUAL, motorSuctionSPDesign=@MOTORSUCTIONSPDESIGN, motorSuctionSPActual=@MOTORSUCTIONSPACTUAL, motorDischargeSPDesign=@MOTORDISCHARGESPDESIGN, motorDischargeSPActual=@MOTORDISCHARGESPACTUAL, motorPreheatCoilSPDesign=@MOTORPREHEATCOILSPDESIGN, motorPreheatCoilSPActual=@MOTORPREHEATCOILSPACTUAL, motorCoolingCoilSPDesign=@MOTORCOOLINGCOILSPDESIGN, motorCoolingCoilSPActual=@MOTORCOOLINGCOILSPACTUAL, motorReheatCoilSPDesign=@MOTORREHEATCOILSPDESIGN, motorReheatCoilSPActual=@MOTORREHEATCOILSPACTUAL, motorFilterSPDesign=@MOTORFILTERSPDESIGN, motorFilterSPActual=@MOTORFILTERSPACTUAL, motorAfterFilterSPDesign=@MOTORAFTERFILTERSPDESIGN, motorAfterFilterSPActual=@MOTORAFTERFILTERSPACTUAL, motorWheelSPDesign=@MOTORWHEELSPDESIGN, motorWheelSPActual=@MOTORWHEELSPACTUAL, remarks=@REMARKS WHERE unit_ID = " + reportID; string sqlConnectionString = "Removed for Security"; using (SqlConnection connection1 = new SqlConnection(sqlConnectionString)) { connection1.Open(); using (SqlCommand updateCommand = new SqlCommand(updateStatement, connection1)) { updateCommand.Parameters.AddWithValue("@UNITMAKE", unitMake); updateCommand.Parameters.AddWithValue("@UNITMODEL", unitModel); updateCommand.Parameters.AddWithValue("@UNITTYPE", unitType); updateCommand.Parameters.AddWithValue("@UNITSIZE", unitSize); updateCommand.Parameters.AddWithValue("@UNITSERIAL", unitSerial); updateCommand.Parameters.AddWithValue("@UNITARRANGEMENT", unitArrangement); updateCommand.Parameters.AddWithValue("@UNITCLASS", unitClass); updateCommand.Parameters.AddWithValue("@UNITDISCHARGE", unitDischarge); updateCommand.Parameters.AddWithValue("@UNITMS", unitMS); updateCommand.Parameters.AddWithValue("@UNITSD", unitSD); updateCommand.Parameters.AddWithValue("@UNITSB", unitSB); updateCommand.Parameters.AddWithValue("@UNITBELTNUMBER", unitBeltNumber); updateCommand.Parameters.AddWithValue("@UNITBELTSIZE", unitBeltSize); updateCommand.Parameters.AddWithValue("@UNITFILTERNUMBER", unitFilterNumber); updateCommand.Parameters.AddWithValue("@UNITFILTERSIZE", unitFilterSize); updateCommand.Parameters.AddWithValue("@UNITTOTALCFMDESIGN", unitTotalCFMDesign); updateCommand.Parameters.AddWithValue("@UNITTOTALCFMACTUAL", unitTotalCFMActual); updateCommand.Parameters.AddWithValue("@UNITRETURNAIRCFMDESIGN", unitReturnAirCFMDesign); updateCommand.Parameters.AddWithValue("@UNITRETURNAIRCFMACTUAL", unitReturnAirCFMActual); updateCommand.Parameters.AddWithValue("@UNITOUTSIDEAIRCFMDESIGN", unitOutsideAirCFMDesign); updateCommand.Parameters.AddWithValue("@UNITOUTSIDEAIRCFMACTUAL", unitOutsideAirCFMActual); updateCommand.Parameters.AddWithValue("@UNITEXHAUSTAIRCFMDESIGN", unitExhaustAirCFMDesign); updateCommand.Parameters.AddWithValue("@UNITEXHAUSTAIRCFMACTUAL", unitExhaustAirCFMActual); updateCommand.Parameters.AddWithValue("@UNITFANRPMDESIGN", unitFanRPMDesign); updateCommand.Parameters.AddWithValue("@UNITFANRPMACTUAL", unitFanRPMActual); updateCommand.Parameters.AddWithValue("@UNITMOTORRPMDESIGN", unitMotorRPMDesign); updateCommand.Parameters.AddWithValue("@UNITMOTORRPMACTUAL", unitMotorRPMActual); updateCommand.Parameters.AddWithValue("@UNITMOTORVOLTSDESIGN", unitMotorVoltsDesign); updateCommand.Parameters.AddWithValue("@UNITMOTORVOLTSACTUAL", unitMotorVoltsActual); updateCommand.Parameters.AddWithValue("@UNITMOTORAMPSDESIGN", unitMotorAmpsDesign); updateCommand.Parameters.AddWithValue("@UNITMOTORAMPSACTUAL", unitMotorAmpsActual); updateCommand.Parameters.AddWithValue("@MOTORMAKE", motorMake); updateCommand.Parameters.AddWithValue("@MOTORFRAME", motorFrame); updateCommand.Parameters.AddWithValue("@MOTORHP", motorHP); updateCommand.Parameters.AddWithValue("@MOTORRPM", motorRPM); updateCommand.Parameters.AddWithValue("@MOTORVOLTS", motorVolts); updateCommand.Parameters.AddWithValue("@MOTORPHASEHZ", motorPhaseHz); updateCommand.Parameters.AddWithValue("@MOTORFULLLOADAMPS", motorFullLoadAmps); updateCommand.Parameters.AddWithValue("@MOTORSF", motorSF); updateCommand.Parameters.AddWithValue("@MOTORMAKESHEAVE", motorMakeSheave); updateCommand.Parameters.AddWithValue("@MOTORSHEAVEDIAMETER", motorSheaveDiameter); updateCommand.Parameters.AddWithValue("@MOTORSHEAVEBORE", motorSheaveBore); updateCommand.Parameters.AddWithValue("@MOTOROPERATINGDIAMETER", motorOperatingDiameter); updateCommand.Parameters.AddWithValue("@MOTORSHEAVECDISTANCE", motorSheaveCDistance); updateCommand.Parameters.AddWithValue("@MOTORTOTALSPDESIGN", motorTotalSPDesign); updateCommand.Parameters.AddWithValue("@MOTORTOTALSPACTUAL", motorTotalSPActual); updateCommand.Parameters.AddWithValue("@MOTORENTERINGSPDESIGN", motorEnteringSPDesign); updateCommand.Parameters.AddWithValue("@MOTORENTERINGSPACTUAL", motorEnteringSPActual); updateCommand.Parameters.AddWithValue("@MOTORSUCTIONSPDESIGN", motorSuctionSPDesign); updateCommand.Parameters.AddWithValue("@MOTORSUCTIONSPACTUAL", motorSuctionSPActual); updateCommand.Parameters.AddWithValue("@MOTORDISCHARGESPDESIGN", motorDischargeSPDesign); updateCommand.Parameters.AddWithValue("@MOTORDISCHARGESPACTUAL", motorDischargeSPActual); updateCommand.Parameters.AddWithValue("@MOTORPREHEATCOILSPDESIGN", motorPreheatCoilSPDesign); updateCommand.Parameters.AddWithValue("@MOTORPREHEATCOILSPACTUAL", motorPreheatCoilSPActual); updateCommand.Parameters.AddWithValue("@MOTORCOOLINGCOILSPDESIGN", motorCoolingCoilSPDesign); updateCommand.Parameters.AddWithValue("@MOTORCOOLINGCOILSPACTUAL", motorCoolingCoilSPActual); updateCommand.Parameters.AddWithValue("@MOTORREHEATCOILSPDESIGN", motorReheatCoilSPDesign); updateCommand.Parameters.AddWithValue("@MOTORREHEATCOILSPACTUAL", motorReheatCoilSPActual); updateCommand.Parameters.AddWithValue("@MOTORFILTERSPDESIGN", motorFilterSPDesign); updateCommand.Parameters.AddWithValue("@MOTORFILTERSPACTUAL", motorFilterSPActual); updateCommand.Parameters.AddWithValue("@MOTORAFTERFILTERSPDESIGN", motorAfterFilterSPDesign); updateCommand.Parameters.AddWithValue("@MOTORAFTERFILTERSPACTUAL", motorAfterFilterSPActual); updateCommand.Parameters.AddWithValue("@MOTORWHEELSPDESIGN", motorWheelSPDesign); updateCommand.Parameters.AddWithValue("@MOTORWHEELSPACTUAL", motorWheelSPActual); updateCommand.Parameters.AddWithValue("@REMARKS", remarks); updateCommand.ExecuteNonQuery(); } connection1.Close(); } }
如果不保护Page_Load不会重新执行填充文本框的代码，则ASP.NET页面生命周期会导致这种情况。
if (!IsPostBack) { string selectStatement = "SELECT * FROM ahu_data WHERE unit_ID = " + reportID; string sqlConnectionString = "Removed for Security"; using (SqlConnection connection1 = new SqlConnection(sqlConnectionString)) { .... rest of code that pre-fill your fields
Page.IsPostBack是Page的布尔属性，如果第一次调用页面或者由于某些需要在服务器端处理的事件而调用它，则会通知您的代码。
在后一种情况下，您不应再次执行填充文本框的代码，否则，当流程到达您的按钮代码时，您将找到具有原始值而不是修改后的值的文本框，因为Page_Load已重置所有内容。
不要忘记上面关于参数化第一个查询的评论。 您已经完成了参数化UPDATE的最大部分，只剩下一个参数并且它已完成。
更新工作正常，问题是它使用的是表中已有的相同数据，所以它不会改变任何东西。
单击“保存”按钮时，页面将执行回发以在服务器上运行代码。 首先， Page_Load事件运行并加载将替换您在表单中输入的数据的原始数据。 然后运行SaveReportButton_Click事件来更新记录。
为了防止Page_Load事件处理程序替换表单中的数据，您应该使用isPostBack属性来检查页面是否由于回发而加载：
if (!IsPostBack) { // load the data from the database in here }