SQL Server：UPDATE不使用C＃更新數據庫

Question

我有一個上面帶有Web表單的網頁。 該表單已預填充了SQL Server數據庫中的數據。 用戶可以進入並編輯任何字段，然后單擊底部的“保存”按鈕以更新數據庫中的記錄。 由於某種原因，當我將表格預先填充數據時，update語句不會更新數據庫中的記錄。 如果我刪除了頁面加載方法上預先填寫表單的代碼，則update語句將按預期工作。 當我在頁面加載方法中用表格預先填充數據時，update語句似乎正在使用記錄中已有的相同數據（而不是用戶輸入的新信息）更新記錄。 我完全不知道如何解決此問題，因為表單必須預先加載數據，以便用戶可以分別編輯表單。

有人可以指出我需要做的錯誤或更正嗎？ 我碰到了眾所周知的磚牆:(

在下面，您將找到頁面加載方法和保存按鈕click事件處理程序。

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();
    }
}

這是保存按鈕單擊處理程序，用於更新數據庫中的記錄。

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();
        }
}

Answer 1

如果您不保護Page_Load避免重新執行填充文本框的代碼，則ASP.NET頁面生命周期會導致這種情況。

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的布爾屬性，用於通知您的代碼是第一次調用該頁面還是由於某些需要在服務器端處理的事件而調用該頁面。
在后一種情況下，您不應再次執行填充文本框的代碼，否則，當流程到達您的按鈕代碼時，您會發現具有原始值的文本框而不是修改后的文本框，因為Page_Load已重置了所有內容。

並且不要忘記上面關於參數化第一個查詢的評論。 您已經完成了參數化UPDATE的大部分工作，僅剩下一個參數即可完成。

Answer 2

更新工作正常，問題在於它使用的是表中已經存在的相同數據，因此它不會更改任何內容。

當您單擊保存按鈕時，頁面將執行回發以在服務器上運行代碼。 首先， Page_Load事件運行並加載原始數據，該數據將替換您在表單中輸入的數據。 然后，運行SaveReportButton_Click事件以更新記錄。

為了防止Page_Load事件處理程序替換表格中的數據，應使用isPostBack屬性檢查是否由於回發而加載了頁面：

if (!IsPostBack) {
  // load the data from the database in here
}