protected override Expression BuildExpression(FilterParameters parameters)
{
var systemEvent = parameters.GetParameter(typeof(SystemEvent));
var propertyName = ExtendedProperties.GetExtendedProperty("property");
var propertyExpression = Expression.Property(systemEvent, propertyName);
return(expressionBuilder.Invoke(
ConvertPropertyValueIfRequired(propertyExpression),
GetConvertedValue(propertyExpression.Type)
));
}
protected Expression GetConvertedValue(Type targetType)
{
var value = ExtendedProperties.GetExtendedProperty("value") ?? String.Empty;
if (targetType.IsEnum)
{
return(Expression.Constant(((IConvertible)Enum.Parse(targetType, value, true)).ToType(targetType.GetEnumUnderlyingType(), CultureInfo.InvariantCulture)));
}
return(typeof(IConvertible).IsAssignableFrom(targetType)
? Expression.Constant(((IConvertible)value).ToType(targetType, CultureInfo.InvariantCulture))
: Expression.Convert(Expression.Constant(value), targetType) as Expression);
}