C# 如何从模式对话框在主窗口中设置变量

对于我愚蠢的问题我很抱歉，但是我被卡住了。我正在创建应用程序，它将使用SQL。在主窗口中，我有一个DataGrid，它显示SQL查询的结果。我想在模式对话框中设置查询。我已经创建了它，但我不知道如何将模态对话框中文本框中的字符串连接到主窗口中的字符串

从此窗口分配字符串查询：

public partial class DB_conn_win : Window
    {
        public DB_conn_win()
        {
            InitializeComponent();
        }

        private void ask_DB_Click(object sender, RoutedEventArgs e)
        {
            string query = textBox1.Text();
        }
.....
}

到主窗口

public partial class MainWindow : Window
{

    string DB_query = DB_conn_win.query;


    public MainWindow()
    {
        InitializeComponent();
 .....

非常感谢你的帮助

public partial class DB_conn_win : Window 
{ 

    private void ask_DB_Click(object sender, RoutedEventArgs e) 
    { 
        this.Query = textBox1.Text(); 
    } 
    public string Query;
..... 
} 



public partial class MainWindow : Window 
{ 

  string DB_query = DB_conn_win.query; 

  public SomeButton_Click(object sender, RoutedEventArgs e)
  {
     var dialog = new DB_conn_win();
     if (dialog.ShowDialog() == true)
     {
       this.DB_query = dialog.Query;
     }
  }

---

ShowDialog和DialogResult检查取决于对话框的设置方式-有关详细信息，请参阅。

不应使用公共字段。也不应使用公共字段，这是属性的用途。

public partial class DB_conn_win : Window { 
    public string query;
    private void ask_DB_Click(object sender, RoutedEventArgs e) { 
        this.query = textBox1.Text(); 
    } 
}

public partial class MainWindow : Window {
    string DB_query;

    public MainWindow() {
        InitializeComponent();
        Loaded += Window_Loaded;
    }

    void Window_Loaded(object sender, RoutedEventArgs e) {
        DB_conn_win dialog = new DB_conn_win();
        dialog.Owner = this;
        dialog.ShowDialog();
        if (dialog.DialogResult != null && dialog.DialogResult.Value)
            DB_Query = dialog.query;
     }   
}