public object ConvertType(object value, Type conversionType, IFormatProvider provider)
{
var request = new ConvertTypeRequest(value, conversionType, provider);
// Don't create unneccessary garbage; instantiate when the first Exception is caught.
List <Exception> exceptions = null;
foreach (var typeConverter in _typeConverters)
{
try
{
typeConverter.Convert(request);
if (request.IsConverted)
{
return(request.ConvertedValue);
}
}
catch (Exception exception) { (exceptions ?? (exceptions = new List <Exception>())).Add(exception); }
}
if (exceptions?.Count > 0)
{
throw new AggregateException(exceptions);
}
else
{
throw new ArgumentException("TODO", nameof(conversionType));
}
}
protected ConvertTypeRequest Convert(object value, Type conversionType, IFormatProvider provider)
{
var request = new ConvertTypeRequest(value, conversionType, provider);
_typeConverter.Convert(request);
return(request);
}
public void Convert(ConvertTypeRequest request)
{
if (request == null)
{
throw new ArgumentNullException(nameof(request));
}
if (request.Value == null && request.ConversionTypeAllowsNull)
{
request.Converted(null);
}
}
public void Convert(ConvertTypeRequest request)
{
if (request == null)
{
throw new ArgumentNullException(nameof(request));
}
// All Nullable<T> instances box as their UnderlyingType.
if (request.Value?.GetType() == request.ConversionType.FlattenGenericNullable())
{
request.Converted(request.Value);
}
}
public void Convert(ConvertTypeRequest request)
{
if (request == null)
{
throw new ArgumentNullException(nameof(request));
}
Type conversionType = request.ConversionType.FlattenGenericNullable();
if (request.Value != null && request.Value.GetType().IsEnumUnderlyingType() && conversionType.IsEnum)
{
request.Converted(Enum.ToObject(conversionType, request.Value));
}
}
public void Convert(ConvertTypeRequest request)
{
if (request == null)
{
throw new ArgumentNullException(nameof(request));
}
// System.Convert.ChangeType requires that value implements IConvertible.
// https://docs.microsoft.com/en-us/dotnet/api/system.convert.changetype?view=netstandard-2.0
//
// TODO : Check that ConversionType is supported by IConvertible.
if ((request.Value == null && !request.ConversionType.IsValueType) || request.Value is IConvertible)
{
request.Converted(System.Convert.ChangeType(request.Value, request.ConversionType.FlattenGenericNullable(), request.Provider));
}
}
public void Convert(ConvertTypeRequest request)
{
if (request == null)
{
throw new ArgumentNullException(nameof(request));
}
if ((request.Value as string)?.Length == 0)
{
if (request.ConversionType == typeof(string))
{
request.Converted(request.Value);
}
else if (request.ConversionTypeAllowsNull)
{
request.Converted(null);
}
}
}
static void Assert(ConvertTypeRequest request)
{
request.IsConverted.Should().BeFalse();
request.ConvertedValue.Should().BeNull();
}
