complete login function and login window also add attached properties and helper classes for securestring

Server Dashboard/AttachedProperty/PasswordBoxProperties.cs

@@ -0,0 +1,30 @@
+using System;
+using System.Collections.Generic;
+using System.Text;
+using System.Windows;
+using System.Windows.Controls;
+
+namespace Server_Dashboard {
+    public class MonitorPasswordProperty : BaseAttachedProperty<MonitorPasswordProperty, bool> {
+        public override void OnValueChanged(DependencyObject sender, DependencyPropertyChangedEventArgs e) {
+            var passwordBox = sender as PasswordBox;
+            if (passwordBox == null)
+                return;
+            passwordBox.PasswordChanged -= PasswordBox_PasswordChanged;
+
+            if ((bool)e.NewValue) {
+                HasTextProperty.SetValue(passwordBox);
+                passwordBox.PasswordChanged += PasswordBox_PasswordChanged;
+            }
+        }
+
+        private void PasswordBox_PasswordChanged(object sender, RoutedEventArgs e) {
+            HasTextProperty.SetValue((PasswordBox)sender);
+        }
+    }
+    public class HasTextProperty : BaseAttachedProperty<HasTextProperty, bool> {
+        public static void SetValue(DependencyObject sender) {
+            SetValue(sender, ((PasswordBox)sender).SecurePassword.Length < 1);
+        }
+    }
+}