TextChangedEvent在文本框更改与否时不会触发

Question

我很难确定我在这里做错了什么。我的逻辑是只有在文本框发生变化时才运行存储过程（UpdateRate）。如果文本框中没有更改，则跳过该行信息的存储过程并移至下一个。

有人能帮我解决这个问题吗？我已经尝试了一切。请记住，我是新手，可能无法完全理解复杂的答案。

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"/> 

我已经设置2个断点内内btnSave_Click的if语句，启动了解决方案，改变了文本框和通知的一个无论我做什么，这两个语句都会导致True。即使我禁用我的文本框并单击保存按钮，我仍然得到True而不是False。当我尝试调试我注意到下面的错误的TextChangedEvent，为我改变文本框的一个：

我真的很感激任何建议。谢谢！

尝试基于@ user2107843答案。它解决了我最初的问题，但是当我第二次单击保存时，它将运行两个存储过程，而不是只更改一个。所以，如果我更改txtAHW然后单击保存，它将起作用，它只运行txtAHW的存储过程。如果在此之后我也改变了txtOHW，则存储过程为两者运行，而不是仅为txtOHW运行。我的逻辑是txtAHW已经被保存了，所以不需要再次运行。可一些帮助我提高了这一点：

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

你应该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; 
     }