private static object ConvertValueImpl(object value, Type targetType, out XamlConvertException exception)
{
try
{
exception = null;
// Target type is undefined or type of object
if (targetType == null || targetType == typeof(object))
{
return(value);
}
// Unset or null value
if (value == null || value.IsUnset())
{
return(targetType.CreateDefaultValue());
}
var valueType = value.GetType();
// No conversion is needed
if (targetType.IsAssignableFrom(valueType))
{
return(value);
}
// Primitive converter
var primitiveConverter = value.GetConverter(targetType);
if (primitiveConverter != null)
{
return(primitiveConverter.Convert(value, CultureInfo.InvariantCulture));
}
var typeDescriptorContext = DummyTypeDescriptorContext.TypeDescriptorInstance;
// Target Type converter
var converter = TypeConversionUtil.GetTypeConverter(targetType);
if (converter?.CanConvertFrom(typeDescriptorContext, valueType) == true)
{
return(converter.ConvertFrom(typeDescriptorContext, CultureInfo.InvariantCulture, value));
}
// Source Type converter
converter = TypeConversionUtil.GetTypeConverter(valueType);
if (converter?.CanConvertTo(typeDescriptorContext, targetType) == true)
{
return(converter.ConvertTo(typeDescriptorContext, CultureInfo.InvariantCulture, value, targetType));
}
// Xaml converter
converter = XamlTypeConverter.GetConverter(targetType);
if (converter?.CanConvertFrom(typeDescriptorContext, valueType) == true)
{
return(converter.ConvertFrom(typeDescriptorContext, CultureInfo.InvariantCulture, value));
}
exception = CreateException(value, targetType, $"Can not convert value '{value}' to type {targetType}");
}
catch (Exception e)
{
exception = CreateException(value, targetType, e);
}
return(null);
}
