private Action <TSource, object[], object> ForProperty(MemberInfo lastMember)
{
var parSource = Expression.Parameter(typeof(TSource));
var getBase = GetFunctionBuilder <TSource> .GetFunction(m_pathItems.Take(m_pathItems.Count - 1).ToList());
if (lastMember is FieldInfo)
{
var fieldLastMember = (FieldInfo)lastMember;
return((source, indexes, value) => fieldLastMember.SetValue(getBase(source, indexes), value));
}
var propLastMember = (PropertyInfo)lastMember;
if (propLastMember != null && propLastMember.CanWrite)
{
return((source, indexes, value) => propLastMember.SetValue(getBase(source, indexes), value));
}
if (propLastMember != null && !propLastMember.CanWrite)
{
var backFieldName = $"<{propLastMember.Name}>i__Field";
var backField = propLastMember
.DeclaringType
.GetFields(BindingFlags.NonPublic | BindingFlags.Instance)
.FirstOrDefault(f => f.Name == backFieldName);
return((source, indexes, value) => backField.SetValue(getBase(source, indexes), value));
}
return(null);
}
private Action <TSource, object[], object> ForArray(Type lastArray)
{
var parSource = Expression.Parameter(typeof(TSource));
var parIndexes = Expression.Parameter(typeof(object[]));
var parValue = Expression.Parameter(typeof(object));
Expression newValue;
Expression lastIndexValue = Expression.Call(s_lastIndex, Expression.Convert(parIndexes, typeof(IEnumerable <object>)));
if (lastArray.Name == "IDictionary`2")
{
lastIndexValue = Expression.Convert(lastIndexValue, lastArray.GenericTypeArguments[0]);
newValue = Expression.Convert(parValue, lastArray.GenericTypeArguments[1]);
}
else
{
lastIndexValue = Expression.Convert(lastIndexValue, typeof(int));
newValue = Expression.Convert(parValue, lastArray.GenericTypeArguments[0]);
}
var baseExpress = GetFunctionBuilder <TSource> .GetFunctionExpression(parSource, parIndexes, m_pathItems.Take(m_pathItems.Count - 1).ToList());
var body = Expression.Assign(
Expression.MakeIndex(baseExpress, lastArray.GetProperty("Item"), new[] { lastIndexValue }),
newValue);
return((Action <TSource, object[], object>)Expression.Lambda(typeof(Action <TSource, object[], object>),
body, parSource, parIndexes, parValue).Compile());
}
public void PrepareForIndexing()
{
m_indexCount = m_items.Where(x => x.Array != null).Count();
m_get = GetFunctionBuilder <TSource> .GetFunction(m_items);
m_set = new SetFunctionBuilder <TSource>(m_items).Build();
m_available = new ExistFunctionBuilder <TSource>(m_items).Build();
m_indexes = new IndexesFunctionBuilder <TSource>(m_items).Build();
}