Dark-Mode-Forms

Apply Dark Mode to all Controls in a Form [WinForms]

This will detect if dark mode color is enabled in Windows settings.
Then iterate all the controls on your form and try to convert them to DarkMode (if enabled).
[Optional] If you have icons on your menus or toolbars, they will be recolored to give you a lighter, more visible-in-the-dark version of your icons. (Works best with monochrome icons)
You can access Windows Dark Colors and use them for whatever you need.

Now with Dark Messenger

Window's default MessageBox cant not be themed, so Added a Messenger.cs class that allowes the user to popup Messages and InputBoxes:

Messenger.MessageBox is a Direct replacement for the old MessageBox.Show, the new one applies Windows's Dark Mode automaticaly.
Messenger.InputBox is a replacement for VisualBasic's InputBox, implemented for C# and with extended functionalities:
- In its simplies form, you ask the user for a Text Input, then you use that for whatever you need
- But Messenger.InputBox allowes you to promt the user with many more 'Fields' of different types:
Button Texts are automatically translated to 7 Languages: en, es, de, fr, ru, kr, zh.
DarkMode doesnt require the Messenger but Messenger does require DarkMode.

MessageBox:

try
{
   if (Messenger.MessageBox("Hello World!", "You got a Message:",
       MessageBoxButtons.OKCancel, MessageBoxIcon.Exclamation) == DialogResult.OK)
   {
      //Do Something here.
   }
}
catch (Exception ex)
{
   Messenger.MessageBox(ex);
}

InputBox:

// Definition of a Single Field:
var BoolControl = new KeyValue("Boolean", "true", KeyValue.ValueTypes.Boolean);

// Can Validate User Inputs on the Field:
BoolControl.Validate += (object? _control, KeyValue.ValidateEventArgs _e) =>
{
   string OldValue = _e.OldValue;
   if (_e.NewValue == "False")
   {
      //_e.Cancel = true; //<- CAN CANCEL THE MODIFICATION
      _e.ErrorText = "No puede ser Falso!";
   }
};

// Custom Values for 'Dynamic' Fields:
List<KeyValue> Dtypes = new List<KeyValue>
{
   new KeyValue("RichText Format", "0"),
   new KeyValue("Plain Text",      "1"),
   new KeyValue("AccountManager",  "2")
};

// Definition of Multiple Fields:
List<KeyValue> _Fields = new List<KeyValue>
{
   new KeyValue("String",  "String",   KeyValue.ValueTypes.String),
   new KeyValue("Password","Password", KeyValue.ValueTypes.Password),
   new KeyValue("Integer", "1000",     KeyValue.ValueTypes.Integer),
   new KeyValue("Decimal", "3,141638", KeyValue.ValueTypes.Decimal),
   BoolControl,
   new KeyValue("Dynamic", "1",        KeyValue.ValueTypes.Dynamic, Dtypes),
};

// Dialog Show:
if (Messenger.InputBox("Custom InputBox", "Please Fill the Form:", ref _Fields,
    MsgIcon.Edit, MessageBoxButtons.OKCancel) == DialogResult.OK)
{
   Debug.WriteLine(string.Format("The New Password is: '{0}'", _Fields[0].Value));
}

Example of a LoginForm with Password Validation:

List<KeyValue> _Fields = new List<KeyValue>
{
   new KeyValue("User Name", "user", KeyValue.ValueTypes.String),
   new KeyValue("Password",  string.Empty, KeyValue.ValueTypes.Password)
};

// Can Validate All the Controls before Closing the Dialog:
Messenger.ValidateControls += (object? sender, CancelEventArgs e) =>
{
   string _userName = _Fields[0].Value;
   string _password = _Fields[1].Value;

   //TODO: Here you should send the User/Password to your BackEnd for Validation
   if (_password != "password")
   {
      _Fields[1].ErrorText = "Incorrect Password!";
      e.Cancel = true; //<- Prevents the Dialog to be closed until is valid
   }
};

// Dialog Show:
if (Messenger.InputBox("Login", "Please Input your Credentials:", ref _Fields,
 MsgIcon.Lock, MessageBoxButtons.OKCancel) == DialogResult.OK)
{
   Messenger.MessageBox(string.Format("The User '{0}' is Logged!", _Fields[0].Value), "Login Correct!",
      MessageBoxButtons.OK, MessageBoxIcon.Exclamation);
}

Implementation

No Nuggets, No external DLLs, Just 1 File: DarkModeCS.cs Copy/Paste or Download and import it into your project.
1 Line to implement it:

public Form1()
{
   InitializeComponent();
   _ = new DarkModeCS(this); //<- Line of code here
}

Dark Mode Colors

Framework Compatibility

.NET 4.8+
.NET 6.0+
Some stuff may only work on Windows 11+
VS 2022+

Limitations

There are a few Winforms Controls that are, by design, extremely hard to theme:

ComboBox: Borders & Dropdown Button look too white. You could use FlatComboBox instead, check in the Example.
TabControl: 90% themed, a white border around the selected tab still remains. You could use FlatTabControl instead, check in the Example.
MessageBox: Can't be themed. You can use Messenger instead.
DateTimePicker: Un-themed.
MonthCalendar: Un-themed.
ProgressBar: Un-themed. You can use FlatProgressBar instead.

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