Toggle system databases visibility

src/SSMSTools/Commands/MultiDbQueryRunner/MultiDbQueryRunnerCommand.cs

@@ -119,13 +119,12 @@ internal void Execute(object sender, EventArgs e)
                 var connectionDatabases = GetDatabasesFromConnection(connection.ConnectionString);
                 if (!connectionDatabases.Any())
                 {
-                    // Show a message box to prove we were here
                     _messageManager.ShowMessageBox(this.package, title, "The connection has no available databases");
                     return;
                 }
 
                 serverInformation.ServerName = connection.ServerName;
-                serverInformation.Databases = connectionDatabases.Select(x => new CheckboxItem { Name = x });
+                serverInformation.Databases = connectionDatabases.Select(x => new CheckboxItem { Name = x }).ToArray();
             }
             catch(OnlyOneObjectExplorerNodeAllowedException)
             {

src/SSMSTools/Models/CheckboxItem.cs

@@ -5,6 +5,7 @@ namespace SSMSTools.Models
     public class CheckboxItem : INotifyPropertyChanged
     {
         private bool _isSelected;
+        private bool _isVisible;
 
         public string Name { get; set; }
 
@@ -18,6 +19,16 @@ public bool IsSelected
             }
         }
 
+        public bool IsVisible
+        {
+            get => _isVisible;
+            set
+            {
+                _isVisible = value;
+                OnPropertyChanged(nameof(IsVisible));
+            }
+        }
+
         public event PropertyChangedEventHandler PropertyChanged;
         protected void OnPropertyChanged(string propertyName) =>
             PropertyChanged?.Invoke(this, new PropertyChangedEventArgs(propertyName));

src/SSMSTools/Models/ConnectedServerInformation.cs

@@ -1,11 +1,11 @@
 using System.Collections.Generic;
-using System.Linq;
+using System.Collections.ObjectModel;
 
 namespace SSMSTools.Models
 {
     public class ConnectedServerInformation
     {
         public string ServerName { get; set; }
-        public IEnumerable<CheckboxItem> Databases { get; set; } = Enumerable.Empty<CheckboxItem>();
+        public ICollection<CheckboxItem> Databases { get; set; } = new Collection<CheckboxItem>();
     }
 }

src/SSMSTools/Windows/MultiDbQueryRunner/MultiDbQueryRunnerWindow.xaml

@@ -3,7 +3,7 @@
         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:SSMSTools.Windows.MultiDbQueryRunner" Height="496.054" Width="420.811"
+        xmlns:local="clr-namespace:SSMSTools.Windows.MultiDbQueryRunner" Height="540.721" Width="420.811"
         >
     <Grid Margin="0,0,0,-188">
         <StackPanel Margin="10">
@@ -26,6 +26,11 @@
                 Databases:
             </Label>
             <!-- Select All Checkbox -->
+            <CheckBox Content="Show system databases"
+                  IsChecked="{Binding IsShowSystemDatabasesSelected, Mode=TwoWay}"
+                      FontSize="12"
+                  Margin="0,0,0,10"/>
+            <!-- Select All Checkbox -->
             <CheckBox Content="Select All"
                   IsChecked="{Binding IsAllSelected, Mode=TwoWay}"
                       FontSize="12"
@@ -37,7 +42,18 @@
                     <ItemsControl.ItemTemplate>
                         <DataTemplate>
                             <CheckBox Content="{Binding Name}"
-                                  IsChecked="{Binding IsSelected, Mode=TwoWay}"/>
+                                  IsChecked="{Binding IsSelected, Mode=TwoWay}">
+                                <CheckBox.Style>
+                                    <Style TargetType="CheckBox">
+                                        <Setter Property="Visibility" Value="Visible"/>
+                                        <Style.Triggers>
+                                            <DataTrigger Binding="{Binding IsVisible}" Value="False">
+                                                <Setter Property="Visibility" Value="Collapsed"/>
+                                            </DataTrigger>
+                                        </Style.Triggers>
+                                    </Style>
+                                </CheckBox.Style>
+                            </CheckBox>
                         </DataTemplate>
                     </ItemsControl.ItemTemplate>
                 </ItemsControl>

src/SSMSTools/Windows/MultiDbQueryRunner/MultiDbQueryRunnerWindow.xaml.cs

@@ -4,6 +4,7 @@
 using SSMSTools.Models;
 using SSMSTools.Windows.Interfaces;
 using System;
+using System.Collections.Generic;
 using System.Collections.ObjectModel;
 using System.ComponentModel;
 using System.Linq;
@@ -17,11 +18,37 @@ public partial class MultiDbQueryRunnerWindow : System.Windows.Window, INotifyPr
         public ObservableCollection<CheckboxItem> Databases { get; private set; }
         public string ServerName { get; private set; }
 
+        private bool _isShowSystemDatabasesSelected;
         private bool _isAllSelected;
         private bool _isUpdating;
         private string _queryContent;
         private readonly DTE2 _dte;
         private readonly IMessageManager _messageManager;
+        private readonly ISet<string> _systemDatabases = new HashSet<string>(StringComparer.OrdinalIgnoreCase)
+        {
+            "master",
+            "tempdb",
+            "model",
+            "msdb"
+        };
+
+        public bool IsShowSystemDatabasesSelected
+        {
+            get => _isShowSystemDatabasesSelected;
+            set
+            {
+                if (_isShowSystemDatabasesSelected != value)
+                {
+                    _isShowSystemDatabasesSelected = value;
+                    OnPropertyChanged(nameof(IsShowSystemDatabasesSelected));
+
+                    if (!_isUpdating)
+                    {
+                        UpdateShowSystemDatabases(value);
+                    }
+                }
+            }
+        }
 
         public bool IsAllSelected
         {
@@ -72,6 +99,8 @@ public void SetServerInformation(ConnectedServerInformation serverInformation)
             Databases = new ObservableCollection<CheckboxItem>(serverInformation.Databases);
             foreach (var item in serverInformation.Databases)
             {
+                item.IsVisible = _systemDatabases.Contains(item.Name) ?
+                    _isShowSystemDatabasesSelected : true;
                 item.PropertyChanged += Item_PropertyChanged;
             }
 
@@ -93,6 +122,19 @@ private void Item_PropertyChanged(object sender, PropertyChangedEventArgs e)
             }
         }
 
+        private void UpdateShowSystemDatabases(bool systemDatabasesVisible)
+        {
+            _isUpdating = true;
+            foreach (var item in Databases)
+            {
+                if (_systemDatabases.Contains(item.Name))
+                {
+                    item.IsVisible = systemDatabasesVisible;
+                }
+            }
+            _isUpdating = false;
+        }
+
         private void UpdateAllItemsSelection(bool isSelected)
         {
             // Set the _isUpdating flag to true to prevent recursion
@@ -113,7 +155,7 @@ private void ExecuteButton_Click(object sender, RoutedEventArgs e)
             var content = new StringBuilder();
             foreach (var database in Databases)
             {
-                if (database.IsSelected)
+                if (database.IsSelected && database.IsVisible)
                 {
                     content.Append($"USE {database.Name}\n");
                     content.Append($"Print 'Running query in {database.Name}'\n");