public Expression GetInstanceCustomResolverExpression(TContext context, Expression instanceExpression, object key)
{
ICollection <Expression <Func <TContext, T, object> > > resolvers = null;
if (!InstanceCustomResolverExpressions.TryGetValue(key, out resolvers) || !resolvers.Any())
{
return(null);
}
var generatedResolvers = resolvers.Select(resolver => {
var contextParameter = resolver.Parameters[0];
var entityParameter = resolver.Parameters[1];
var replacementExpressionVisitor = new ReplacementExpressionVisitor(new Dictionary <Expression, Expression>()
{
{ contextParameter, Expression.Constant(context) },
{ entityParameter, instanceExpression }
});
return(replacementExpressionVisitor.Visit(resolver.Body));
});
var firstExpression = generatedResolvers.First();
if (!generatedResolvers.Skip(1).Any())
{
return(firstExpression);
}
Func <Expression, Expression, Expression> reducer = null;
if (!InstanceCustomResolverExpressionReducers.TryGetValue(key, out reducer))
{
reducer = DefaultExpressionReducer;
}
return(generatedResolvers.Skip(1).Aggregate(firstExpression, (expression, resolver) => reducer(expression, resolver)));
}
public Func <Expression, Expression, Expression> GetInstanceCustomExpressionReducer(object key)
{
Func <Expression, Expression, Expression> reducer = null;
if (!InstanceCustomResolverExpressionReducers.TryGetValue(key, out reducer))
{
reducer = DefaultExpressionReducer;
}
return(reducer);
}
