Translating a windows form to WPF

cs file
-------

using System;
using System.Collections.Generic;
using System.Data.OleDb;
using System.Linq;
using System.Text;
using System.Threading.Tasks;
using System.Windows;
using System.Windows.Controls;
using System.Windows.Data;
using System.Windows.Documents;
using System.Windows.Input;
using System.Windows.Media;
using System.Windows.Media.Imaging;
using System.Windows.Navigation;
using System.Windows.Shapes;
using Microsoft.Win32;
using System.Data;

namespace ExcelCookbookReader
{
    /// <summary>
    /// Interaction logic for MainWindow.xaml
    /// </summary>
    public partial class MainWindow : Window
    {
        public MainWindow()
        {
            InitializeComponent();
        }

        private void openFileButton_Click(object sender, RoutedEventArgs e)
        {
            OpenFileDialog openDialog = new OpenFileDialog();
            openDialog.Filter = "Excel files(*.xlsm )|*.xlsm|(*.xlsx )|*.xlsx";
            if (openDialog.ShowDialog() == true)
            {
                excelFileTextBox.Text = openDialog.FileName;
                //Get all worksheet names from the Excel file selected using GetSchema of an OleDbConnection
                string sourceConnectionString = String.Format(@"Provider=Microsoft.ACE.OLEDB.12.0;Data Source={0};Extended Properties='Excel 12.0 Xml;HDR=YES'", excelFileTextBox.Text);
                OleDbConnection connection = new OleDbConnection(sourceConnectionString);
                connection.Open();
                DataTable tables = connection.GetSchema("Tables", new String[] { null, null, null, "TABLE" });
                connection.Dispose();
                //Add each table name to the combo box
                if (tables != null && tables.Rows.Count > 0)
                {
                    worksheetsComboBox.Items.Clear();
                    foreach (DataRow row in tables.Rows)
                    {
                        worksheetsComboBox.Items.Add(row["TABLE_NAME"].ToString());
                    }
                }
            }
        }

        private void worksheetsComboBox_SelectionChanged(object sender, SelectionChangedEventArgs e)
        {
            //Display the data from the selected Worksheet 
            string sourceConnectionString = String.Format(@"Provider=Microsoft.ACE.OLEDB.12.0;Data Source={0};Extended Properties='Excel 12.0 Xml;HDR=YES'", excelFileTextBox.Text);
                        
            OleDbDataAdapter adapter = new OleDbDataAdapter(String.Format("SELECT * FROM [{0}]", worksheetsComboBox.SelectedItem.ToString()), sourceConnectionString);

            DataSet currentSheet = new DataSet();
            adapter.Fill(currentSheet);
            adapter.Dispose();

            exceldataGrid.ItemsSource  = currentSheet.Tables[0].DefaultView;          
        }

        private void closeAppBtn_Click(object sender, RoutedEventArgs e)
        {
            Application App = Application.Current;
            App.Shutdown();
        }
    }
}

XAML
----
<Window x:Class="ExcelCookbookReader.MainWindow"
        xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
        xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
        xmlns:d="http://schemas.microsoft.com/expression/blend/2008"
        xmlns:mc="http://schemas.openxmlformats.org/markup-compatibility/2006"
        xmlns:local="clr-namespace:ExcelCookbookReader"
        mc:Ignorable="d"
        Title="MainWindow" Height="380" Width="560">
    <StackPanel VerticalAlignment="Top">
        <WrapPanel Margin="5,5,5.4,5" Background="LightBlue" Height="35" >
            <Label Content="Excel File:" HorizontalAlignment="Left"/>
            <TextBox x:Name="excelFileTextBox" Margin="7,7,7,7" Width="411"/>
            <Button x:Name="openFileButton"  Click="openFileButton_Click" Margin="5,5,5,5" Width="35"  FontWeight="UltraBold" Content=" ... " RenderTransformOrigin="1.006,0.564"/>
        </WrapPanel>
        <WrapPanel Margin="5,5,5.4,5" Background="PaleGoldenrod" Height="35">
            <Label Content="Worksheets" HorizontalAlignment="Left"/>
            <ComboBox x:Name="worksheetsComboBox"  SelectionChanged="worksheetsComboBox_SelectionChanged" Margin="7,7,7,7" Width="446"/>
        </WrapPanel>
        <StackPanel Margin=" 10" Background="Red" Height="240" VerticalAlignment="Stretch">
            <DataGrid x:Name="exceldataGrid" Height="200" Margin="0,0,-0.4,0"/>
            <WrapPanel HorizontalAlignment="Right">
                <Button x:Name="closeAppBtn" Click="closeAppBtn_Click" Margin="7,10,20,7" Width="60" Content="Close" />
            </WrapPanel>
        </StackPanel>
        
    </StackPanel>
</Window>