public Expression MapExpression(IConfigurationProvider configurationProvider, ProfileMap profileMap,
PropertyMap propertyMap, Expression sourceExpression, Expression destExpression, Expression contextExpression)
{
Expression mapExpr = null;
if (IsDataReader(sourceExpression.Type, destExpression.Type))
{
ParameterExpression itemParam;
Expression itemExpr;
try
{
itemExpr = CollectionMapperExpressionFactory.MapItemExpr(configurationProvider, profileMap, typeof(IEnumerable <IDataRecord>), destExpression.Type, contextExpression, out itemParam);
}
catch (Exception ex)
{
throw new AutoMapperMappingException("Missing type map configuration or unsupported mapping.", ex, new TypePair(sourceExpression.Type, destExpression.Type));
}
if (YieldReturnEnabled)
{
var mapFunc = Lambda(itemExpr, itemParam, contextExpression as ParameterExpression);
MethodInfo genericMapFunc = DataReaderHelper.DataReaderAsYieldReturnMethod.MakeGenericMethod(TypeHelper.GetElementType(destExpression.Type));
var sourceAsYieldReturn = Call(null, genericMapFunc, sourceExpression, contextExpression, mapFunc);
mapExpr =
Block(sourceAsYieldReturn);
}
else
{
var sourceAsEnumerable = Call(null, DataReaderHelper.DataReaderAsEnumerableMethod, sourceExpression);
var listType = typeof(List <>).MakeGenericType(TypeHelper.GetElementType(destExpression.Type)); // Cache this if we experience poor performance
var listVar = Variable(listType, "list");
var listAddExpr = Call(listVar, listType.GetMethod("Add"), itemExpr); // Cache this if we experience poor performance
mapExpr =
Block(new[] { listVar },
Assign(listVar, New(listType)),
ExpressionExtensions.ForEach(sourceAsEnumerable, itemParam, listAddExpr),
listVar);
}
}
return(mapExpr);
}