Add project files.

Challenges/formUpdChallenges.xaml.cs

@@ -0,0 +1,49 @@
+using System.Windows;
+using Npgsql;
+
+namespace SportsTrainingApp.Challenges
+{
+   
+    public partial class formUpdChallenges : Window
+    {
+        formChallenges.Challenges item;
+        public formUpdChallenges(formChallenges.Challenges _item)
+        {
+            InitializeComponent();
+            item = _item;
+            FillFormFields(item);
+        }
+
+        private void FillFormFields(formChallenges.Challenges _item)
+        {
+            tbName.Text = _item.Name;
+            tbDescription.Text = _item.Description;
+            dtEnd.SelectedDate = _item.End_date.Date;
+            dtStart.SelectedDate = _item.Start_date.Date;
+        }
+
+        private void Button_Click_2(object sender, RoutedEventArgs e)
+        {
+            this.Close();
+        }
+
+        private void Button_Click_1(object sender, RoutedEventArgs e)
+        {
+            using (var conn = new NpgsqlConnection(formMain.connectionString))
+            {
+                conn.Open();
+                using (var cmd = new NpgsqlCommand(@$"UPDATE dbo.challenges
+	                                                  SET name=@name, description=@description, start_date=@start_date, end_date=@end_date
+	                                                    WHERE id = {item.ID};", conn))
+                {
+                    cmd.Parameters.AddWithValue("name", tbName.Text);
+                    cmd.Parameters.AddWithValue("description", tbDescription.Text);
+                    cmd.Parameters.AddWithValue("start_date", dtStart.SelectedDate);
+                    cmd.Parameters.AddWithValue("end_date", dtEnd.SelectedDate);
+                    cmd.ExecuteNonQuery();
+                }
+            }
+            this.Close();
+        }
+    }
+}