/// <summary>
/// Translates the Expression tree to a tree of UpdateMembers
/// </summary>
/// <param name="expression">The expression.</param>
/// <returns></returns>
public UpdateMember GetUpdateMembers(Expression <Func <IUpdateConfiguration <T>, object> > expression)
{
var initialNode = new UpdateMember();
currentMember = initialNode;
Visit(expression);
return(initialNode);
}
protected override Expression VisitMethodCall(MethodCallExpression expression)
{
currentMethod = expression.Method.Name;
// go left to right in the subtree (ignore first argument for now)
for (int i = 1; i < expression.Arguments.Count; i++)
{
Visit(expression.Arguments[i]);
}
// go back up the tree and continue
currentMember = currentMember.Parent;
return(Visit(expression.Arguments[0]));
}
public static List <string> GetIncludeStrings(UpdateMember root)
{
var list = new List <string>();
if (root.Members.Count == 0)
{
list.Add(root.IncludeString);
}
foreach (var member in root.Members)
{
list.AddRange(GetIncludeStrings(member));
}
return(list);
}
protected override Expression VisitMember(MemberExpression expression)
{
// Create new node for this item
var newMember = new UpdateMember
{
Members = new Stack <UpdateMember>(),
Parent = currentMember,
Accessor = (PropertyInfo)expression.Member
};
currentMember.Members.Push(newMember);
previousMember = currentMember;
currentMember = newMember;
currentMember.IncludeString = previousMember.IncludeString != null
? previousMember.IncludeString + "." + currentMember.Accessor.Name
: currentMember.Accessor.Name;
// Chose if entity update or reference update and create expression
switch (currentMethod)
{
case "OwnedEntity":
currentMember.IsOwned = true;
break;
case "AssociatedEntity":
currentMember.IsOwned = false;
break;
case "OwnedCollection":
currentMember.IsOwned = true;
currentMember.IsCollection = true;
break;
case "AssociatedCollection":
currentMember.IsOwned = false;
currentMember.IsCollection = true;
break;
default:
throw new NotSupportedException("The method used in the update mapping is not supported");
}
return(base.VisitMember(expression));
}
