將動態值添加到XML中的組合框？

Question

我做了一個程序，它從文本框中的用戶獲取價值，並將該值添加到ComboBox中，該工作正常，但是當我關閉程序時，它丟失了所有信息因爲我沒有使用數組，但現在我希望它應該動態地將值添加到XML關閉程序後永久存儲在哪裏？ plz幫助我，我怎麼能做到這一點

我的C＃代碼

namespace PopupDemo 
 
{ 
 
    public partial class MainWindow : Window 
 
    { 
 
     public MainWindow() 
 
     { 
 
      InitializeComponent(); 
 
     } 
 

 
     private void Show_Click(object sender, RoutedEventArgs e) 
 
     { 
 
      MyPopup.IsOpen = true; 
 
     } 
 

 
     private void Add_Click(object sender, RoutedEventArgs e) 
 
     { 
 

 
      comboBox.Items.Add(textbox.Text); 
 
      MyPopup.IsOpen = false; 
 
     } 
 

 
     private void comboBox_SelectionChanged(object sender, SelectionChangedEventArgs e) 
 
     { 
 

 
     } 
 
    } 
 
}

我的XML代碼

<Window x:Class="PopupDemo.MainWindow" 
 
     xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation" 
 
     xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml" 
 
     Title="ToolTip Demo" 
 
     Height="335.461" 
 
     Width="457.092"> 
 
    <Grid Margin="10"> 
 
     <Button Click="Show_Click" Margin="82,179,68,30">Show Popup</Button> 
 
     <Popup Name="MyPopup" 
 
       Placement="Mouse" 
 
       HorizontalOffset="-100" 
 
       VerticalOffset="-100" 
 
       AllowsTransparency="True" 
 
       
 
       > 
 
      <Grid> 
 
       <Ellipse Width="300" Height="300" Fill="Aquamarine"/> 
 
       <TextBox Width="200" Height="40" Name="textbox" ></TextBox> 
 
       <Button Click="Add_Click" Margin="77,209,63,60" Height="50" Width="150" RenderTransformOrigin="0.532,3.873">Add</Button> 
 
      </Grid> 
 
     </Popup> 
 
     <ComboBox x:Name="comboBox" HorizontalAlignment="Left" Margin="82,63,0,0" VerticalAlignment="Top" Width="279" Height="83" SelectionChanged="comboBox_SelectionChanged"/> 
 
    </Grid> 
 
</Window>

Answer 1

這裏是你如何編寫文本框。文本到XML文件。

//recreates file if there is already one. 
    XmlTextWriter xmlFile = new XmlTextWriter("comboXml.xml", System.Text.UTF8Encoding.UTF8); 


    //intened formatting 
    xmlFile.Formatting = Formatting.Indented; 
    private void Add_Click(object sender, RoutedEventArgs e) 
      { 
       comboBox.Items.Add(textbox.Text); 
      try 
      { 
       xmlFile.WriteStartDocument(); 
       xmlFile.WriteStartElement("myData"); 
       xmlFile.WriteElementString("myAttribute", textbox.Text); 


       xmlFile.WriteEndElement(); 
       xmlFile.Close(); 

      } 
      catch (Exception ex) 
       { 
       MessageBox.Show("Xml Writing Failed:" + ex.Message); 
       } 


       MyPopup.IsOpen = false; 
    } 

，這裏是你如何從XML文件

private void PopulateComboBox() 
    { 
     DataTable dt = new DataTable(); 
     dt.Columns.Add("myAttribute", typeof(string)); 




     XmlTextReader readXml = new XmlTextReader("comboXml.xml"); 
     try 
     { 
      while (readXml.Read()) 
      { 
       if (readXml.NodeType == XmlNodeType.Element) 
       { 
        switch (readXml.Name) 
        { 
         case "myAttribute": 
          DataRow dr = dt.NewRow(); 
          dr["myAttribute"] = readXml.ReadString() ; 
          dt.Rows.Add(dr); 
          break; 
        } 
       } 
      } 

      readXml.Close(); 
     } 
     catch (Exception ex) 
     { 
      Console.WriteLine("Xml connection failed: " + ex.Message); 
     } 


     if (dt.Rows.Count > 0) 
     { 
      comboBox.DataSource = dt; 
      comboBox.ValueMember = "myAttribute"; 
      comboBox.DisplayMember = "myAttribute";  
     } 

     else 
     { 
      MessageBox.Show("No source found!", "Warning"); 
     } 

    } 

填充現在，調用PopulateComboBox上MainWindow_Load事件。完成！