UriTypeConverter.cs

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using System.ComponentModel;
using System.ComponentModel.Design.Serialization;
using System.Globalization;
using System.Reflection;
 
namespace System;
 
public class UriTypeConverter : TypeConverter
{
    public override bool CanConvertFrom(ITypeDescriptorContext? context, Type sourceType)
    {
        if (!(sourceType == typeof(string)) && !(sourceType == typeof(Uri)))
        {
            return base.CanConvertFrom(context, sourceType);
        }
        return true;
    }
 
    public override bool CanConvertTo(ITypeDescriptorContext? context, Type? destinationType)
    {
        if (!(destinationType == typeof(Uri)) && !(destinationType == typeof(InstanceDescriptor)))
        {
            return base.CanConvertTo(context, destinationType);
        }
        return true;
    }
 
    public override object? ConvertFrom(ITypeDescriptorContext? context, CultureInfo? culture, object? value)
    {
        if (value is string text)
        {
            if (string.IsNullOrEmpty(text))
            {
                return null;
            }
            return new Uri(text, UriKind.RelativeOrAbsolute);
        }
        if (value is Uri uri)
        {
            return new Uri(uri.OriginalString, GetUriKind(uri));
        }
        throw GetConvertFromException(value);
    }
 
    public override object ConvertTo(ITypeDescriptorContext? context, CultureInfo? culture, object? value, Type destinationType)
    {
        if (destinationType == null)
        {
            throw new ArgumentNullException("destinationType");
        }
        if (value is Uri uri)
        {
            if (destinationType == typeof(InstanceDescriptor))
            {
                ConstructorInfo constructor = typeof(Uri).GetConstructor(BindingFlags.Instance | BindingFlags.Public, null, new Type[2]
                {
                    typeof(string),
                    typeof(UriKind)
                }, null);
                return new InstanceDescriptor(constructor, new object[2]
                {
                    uri.OriginalString,
                    GetUriKind(uri)
                });
            }
            if (destinationType == typeof(string))
            {
                return uri.OriginalString;
            }
            if (destinationType == typeof(Uri))
            {
                return new Uri(uri.OriginalString, GetUriKind(uri));
            }
        }
        throw GetConvertToException(value, destinationType);
    }
 
    public override bool IsValid(ITypeDescriptorContext? context, object? value)
    {
        if (value is string uriString)
        {
            Uri result;
            return Uri.TryCreate(uriString, UriKind.RelativeOrAbsolute, out result);
        }
        return value is Uri;
    }
 
    private static UriKind GetUriKind(Uri uri)
    {
        if (!uri.IsAbsoluteUri)
        {
            return UriKind.Relative;
        }
        return UriKind.Absolute;
    }
}