TextChangedEvent在文本框更改與否時不會觸發

Question

我很難確定我在這裏做錯了什麼。我的邏輯是隻有在文本框發生變化時才運行存儲過程（UpdateRate）。如果文本框中沒有更改，則跳過該行信息的存儲過程並移至下一個。

有人能幫我解決這個問題嗎？我已經嘗試了一切。請記住，我是新手，可能無法完全理解複雜的答案。

C＃：

public partial class MainWindow : 
{ 
    internal static string oldAvgRate; 
    internal static string oldOTRate; 
    internal static string ratetype; 
    internal static string rtOT; 

    public MainWindow() 
    { 
     InitializeComponent(); 

     string connectionString = "datasource=;port=;username=;password="; 
     string sDate = DateTime.Now.ToString("yyyy-MM-dd"); 
     MySqlConnection connection = new MySqlConnection(connectionString); 

     MySqlCommand avgRate = new MySqlCommand("Select ID, DateFrom, DateTo, RateType, Amount, Description from Daily.Rates where RateType = 'Average Hourly Wages' and DateTo >= @sDate", connection); 
     avgRate.Parameters.Add(new MySqlParameter("sDate", sDate)); 

     MySqlCommand otRate = new MySqlCommand("Select ID, DateFrom, DateTo, RateType, Amount, Description from Daily.Rates where RateType = 'Average OT Hourly Wages' and DateTo >= @sDate", connection); 
     otRate.Parameters.Add(new MySqlParameter("sDate", sDate)); 

     try 
     { 
      connection.Open(); 

      MySqlDataReader AvgR = avgRate.ExecuteReader(); 

      while (AvgR.Read()) 
      { 
       txtAHW.Text = AvgR["Amount"].ToString(); 
       dfAHW.Text = AvgR["DateFrom"].ToString(); 
       dtAHW.Text = AvgR["DateTo"].ToString(); 
       txtcommAHW.Text = AvgR["Description"].ToString(); 

       oldAvgRate = txtAHW.Text = AvgR["Amount"].ToString(); 
       ratetype = AvgR["RateType"].ToString(); 
      } 

      AvgR.Close(); 
      AvgR.Dispose(); 

      MySqlDataReader OtR = otRate.ExecuteReader(); 

      while (OtR.Read()) 
      { 
       txtOTHW.Text = OtR["Amount"].ToString(); 
       dfOTHW.Text = OtR["DateFrom"].ToString(); 
       dtOTHW.Text = OtR["DateTo"].ToString(); 
       txtcommOTHW.Text = OtR["Description"].ToString(); 

       oldOTRate = txtOTHW.Text = OtR["Amount"].ToString(); 
       rtOT = OtR["RateType"].ToString(); 
      } 

      OtR.Close(); 
      OtR.Dispose(); 
     } 

     catch (Exception ex) 
     { 
      MessageBox.Show(ex.Message); 
     } 

     connection.Close(); 
    } 

     private string UpdateRate(string dateFrom, string newRate, string oldRate, string ratetype, string description) 
     { 
      string connectionString = "datasource=;port=;Initial Catalog='';username=;password="; 
      MySqlConnection connection = new MySqlConnection(connectionString); 

      try 
      { 
       connection.Open(); 

       MySqlCommand cmd = new MySqlCommand("UpdateRate", connection); 
       cmd.CommandType = CommandType.StoredProcedure; 
       cmd.Parameters.Add("@p_DateFrom", MySqlDbType.Date).Value = dateFrom; 
       cmd.Parameters.Add("@p_NewAmount", MySqlDbType.Decimal).Value = newRate; 
       cmd.Parameters.Add("@p_OldAmount", MySqlDbType.Decimal).Value = oldRate; 
       cmd.Parameters.Add("@p_RateType", MySqlDbType.VarChar).Value = ratetype; 
       cmd.Parameters.Add("@p_Description", MySqlDbType.VarChar).Value = description; 

       cmd.ExecuteNonQuery();    
       connection.Close(); 
       return newRate;    
      } 

      catch (Exception ex) 
      { 
       MessageBox.Show(ex.Message); 
      } 
      return null; 
     } 

     private bool txtAHWHasChangedFlag; 
     private bool txtOTHWHasChangedFlag; 

     private void textChangedEventHandler(object sender, TextChangedEventArgs args) 
     {   
      var control = sender as TextBox; 

      if (control.Name == "txtAHW") 
       txtAHWHasChangedFlag = true; 
      else if (control.Name == "txtOTHW") 
       txtOTHWHasChangedFlag = true; 
     } 

     private void btnSave_Click(object sender, RoutedEventArgs e) 
     { 
      if (txtAHWHasChangedFlag) //True regardless if changes are made in the textbox or not :(
      { 
      oldAvgRate = UpdateRate(dfAHW.SelectedDate.Value.ToString("yyyy-MM-dd"), txtAHW.Text, oldAvgRate, ratetype, txtcommAHW.Text); 
      MessageBox.Show("Done", "Test", MessageBoxButton.OK); 
      } 

      if (txtOTHWHasChangedFlag) //True regardless if changes are made in the textbox or not :(
      { 
      oldOTRate = UpdateRate(dfOTHW.SelectedDate.Value.ToString("yyyy-MM-dd"), txtOTHW.Text, oldOTRate, rtOT, txtcommOTHW.Text); 
      MessageBox.Show("Done", "Test", MessageBoxButton.OK); 
      } 

      if (!txtAHWHasChangedFlag && !txtOTHWHasChangedFlag) 
      {  
      MessageBox.Show("Nothing has changed", "Test", MessageBoxButton.OK); 
      return; 
      } 
     } 
} 

XAML：

<TextBox x:Name="txtAHW" TextChanged="textChangedEventHandler"/> 
<TextBox x:Name="txtOTHW" TextChanged="textChangedEventHandler"/> 

我已經設置2個斷點內內btnSave_Click的if語句，啓動了解決方案，改變了文本框和通知的一個無論我做什麼，這兩個語句都會導致True。即使我禁用我的文本框並單擊保存按鈕，我仍然得到True而不是False。當我嘗試調試我注意到下面的錯誤的TextChangedEvent，爲我改變文本框的一個：

我真的很感激任何建議。謝謝！

嘗試基於@ user2107843答案。它解決了我最初的問題，但是當我第二次單擊保存時，它將運行兩個存儲過程，而不是隻更改一個。所以，如果我更改txtAHW然後單擊保存，它將起作用，它只運行txtAHW的存儲過程。如果在此之後我也改變了txtOHW，則存儲過程爲兩者運行，而不是僅爲txtOHW運行。我的邏輯是txtAHW已經被保存了，所以不需要再次運行。可一些幫助我提高了這一點：

private void textChangedEventHandler(object sender, TextChangedEventArgs args) 
{   
    var control = sender as TextBox; 

    if (control.Name == "txtAHW") 

     if (oldAvgRate != txtAHW.Text && oldAvgRate != null) 
      txtAHWHasChangedFlag = true; 
     else 
      txtAHWHasChangedFlag = false; 
    else if (control.Name == "txtOTHW") 
     if (oldOTRate != txtOTHW.Text && oldOTRate != null) 
      txtOTHWHasChangedFlag = true; 
     else 
      txtOTHWHasChangedFlag = false; 
} 

Answer 1

你應該textChangedEventHandler

private void textChangedEventHandler(object sender, TextChangedEventArgs args) 
     {   
      var control = sender as TextBox; 

      if (control.Name == "txtAHW") 

       if(oldAvgRate != txtAHW.Text && oldAvgRate !=null) 
        txtAHWHasChangedFlag = true; 
       else 
        txtAHWHasChangedFlag = false 
      else if (control.Name == "txtOTHW") 
       txtOTHWHasChangedFlag = true; 
     }