Using the Data Converters package

The Data Converters package provides a collection of value converters and extensions to manipulate data in your applications.

Converting a DateTime to a String using the DateTimeToStringValueConverter

Value converters are a common coding practice for building XAML applications that allow values to be bound to a view, converted to a different type and back depending on the binding mode.

Why should that be limited to just XAML applications though?

The MADE.Data.Converters.DateTimeToStringValueConverter works across any .NET application, including your XAML bindings.

It converts a DateTime value to a String using a format parameter. The format parameter must be a valid DateTime string format based on the Microsoft documentation.

Below is an example of this in use in any C# application.

namespace App.Conversions
{
    using MADE.Data.Converters;

    public class ApplicationConverters
    {
        private readonly DateTimeToStringValueConverter DateTimeToStringConverter = new DateTimeToStringValueConverter();

        public string ConvertDateToString(DateTime date)
        {
            return DateTimeToStringConverter.Convert(date, "g");
        }

        public DateTime ConvertStringToDate(string dateString)
        {
            return DateTimeToStringConverter.ConvertBack(dateString, "g");
        }
    }
}

You can also take advantage of this converter in your XAML applications too.

<Page
    x:Class="App.Conversions.MainPage"
    xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
    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:converters="using:MADE.Data.Converters"
    Background="{ThemeResource ApplicationPageBackgroundThemeBrush}"
    mc:Ignorable="d">

    <Page.Resources>
        <converters:DateTimeToStringValueConverter x:Key="DateTimeToStringValueConverter" />
    </Page.Resources>

    <RelativePanel Padding="12">
        <TextBlock Text="{x:Bind ViewModel.Date, Converter={StaticResource DateTimeToStringValueConverter}, ConverterParameter='g'}" />
    </RelativePanel>
</Page>

Creating your own custom value converters

If you want to take advantage of what goes into a value converter, you can build your own using the MADE.Data.Converters.IValueConverter interface which provides the signatures for the Convert and ConvertBack methods.

These can be used to convert any type to another. Whatever data conversion you think you may need, you'll be able to build out a value converter to satisfy that need for your project.

You can then build out your own, similar to our DateTimeToStringValueConverter.

namespace MADE.Data.Converters
{
    using System;
    using System.Globalization;

    public partial class DateTimeToStringValueConverter : IValueConverter<DateTime, string>
    {
        public string Convert(DateTime value, object parameter = default)
        {
            string format = parameter?.ToString();
            return !string.IsNullOrWhiteSpace(format)
                       ? value.ToString(format, CultureInfo.InvariantCulture)
                       : value.ToString(CultureInfo.InvariantCulture);
        }

        public DateTime ConvertBack(string value, object parameter = default)
        {
            if (string.IsNullOrWhiteSpace(value))
            {
                return DateTime.MinValue;
            }

            bool parsed = DateTime.TryParse(value, out DateTime dateTime);
            return parsed ? dateTime : DateTime.MinValue;
        }
    }
}

If you want to build a XAML specific value converter, you can also apply the Windows.UI.Xaml.Data.IValueConverter to your class and implement the additional methods calling directly into your Convert and ConvertBack methods.

If there is a common value converter you think is missing from MADE.NET, raise a tracking item on GitHub and we'll get it implemented.