[Proposal] DateTimeOffsetConverter

DateTimeOffsetConverter

• Proposed
• Prototype
• Implementation: Not Started
  • iOS Support
  • Android Support
  • macOS Support
  • Windows Support
• Unit Tests
• Documentation: Not Started
• Sample

Summary

The DateTimeOffsetConverter is a converter that allows users to convert a DateTimeOffset to a DateTime. Sometimes a DateTime value is stored with the offset on a backend to allow for storing the timezone in which a DateTime originated from. Controls like the Microsoft.Maui.Controls.DatePicker only work with DateTime. This converter can be used in those scenarios.

Detailed Design

DateTimeOffsetConverter.shared.cs

public class DateTimeOffsetConverter : ValueConverterExtension, IValueConverter
{
  public object Convert(object? value, Type targetType, object? parameter, System.Globalization.CultureInfo culture)=> value is DateTimeOffset dateTimeOffset
    ? dateTimeOffset.DateTime
    : throw new ArgumentException("Value is not a valid DateTimeOffset", nameof(value));

  public object ConvertBack(object? value, Type targetType, object? parameter, System.Globalization.CultureInfo culture) => value is DateTime dateTime
    ? dateTime.Kind switch
    {
	    DateTimeKind.Local => new DateTimeOffset(dateTime, DateTimeOffset.Now.Offset),
	    DateTimeKind.Utc => new DateTimeOffset(dateTime, DateTimeOffset.UtcNow.Offset),
	    _ => new DateTimeOffset(dateTime, TimeSpan.Zero),
    }
    : throw new ArgumentException("Value is not a valid DateTime", nameof(value));
}

Usage Syntax

XAML Usage

<ContentPage xmlns="http://xamarin.com/schemas/2014/forms"
             xmlns:x="http://schemas.microsoft.com/winfx/2009/xaml"
             xmlns:xct="http://xamarin.com/schemas/2020/toolkit"
             x:Class="MyLittleApp.MainPage">
    <ContentPage.Resources>
         <ResourceDictionary>
             <xct:DateTimeOffsetConverter x:Key="DateTimeOffsetConverter" />
         </ResourceDictionary>
    </ContentPage.Resources>

    <StackLayout>

        <Label Text="{Binding MyDateTimeOffset, Converter={StaticResource DateTimeOffsetConverter}}" />

    </StackLayout>
</ContentPage>

C# Usage

class MyPage : ContentPage
{
  public MyPage()
  {
    Content = new StackLayout
    {
      Children = 
      {
          new Label().Bind(Label.TextProperty, nameof(ViewModel. MyDateTimeOffset), converter: new DateTimeOffsetConverter()),
      };
    }
  }
}

[bijington]

@CliffAgius no you linked it fine. The proposal won’t automatically be closed as a result of the docs PR being closed. We need to manually drag the issue over to the complete column in the Project board. This is down to the fact that a feature/proposal should not be merged before the docs are done. Don’t worry I’ll sort this proposal.

Thanks again for the contribution!

[jfversluis]

O shoot, I should be more aware of if the actual feature is merged as well. My bad. 😬

I guess this one is done now though with the Docs also being complete?