private static T GetMemberValueCore <T>(object origin, MemberToken[] members, Func <MemberGettingContext, MemberGettingResult> resolve, Action <object, MemberToken> onError)
{
var owner = origin;
MemberGettingContext context = null;
foreach (var member in members)
{
if (resolve == null)
{
object memberValue;
if (!TryGetMemberValueCore(owner, member, out memberValue))
{
onError(owner, member);
return(default(T));
}
owner = memberValue;
}
else
{
context = new MemberGettingContext(owner, member, context);
MemberGettingResult result;
if ((result = resolve(context)).Cancel)
{
return((T)result.Value);
}
owner = result.Value;
}
}
return((T)owner);
}
public static void SetMemberValue <T>(object origin, MemberToken[] members, Func <T> valueFactory, Func <MemberGettingContext, object> getter = null, Action <MemberSettingContext <T> > setter = null)
{
if (origin == null)
{
throw new ArgumentNullException(nameof(origin));
}
if (members == null)
{
throw new ArgumentNullException(nameof(members));
}
if (valueFactory == null)
{
throw new ArgumentNullException(nameof(valueFactory));
}
if (members.Length == 0)
{
return;
}
var owner = origin;
MemberGettingContext context = null;
for (int i = 0; i < members.Length - 1; i++)
{
if (getter == null)
{
if (!TryGetMemberValueCore(owner, members[i], out owner))
{
throw new ArgumentException(string.Format("The '{0}' member is not exists in the '{1}' type.", members[i], (owner is Type ? ((Type)owner).FullName : owner.GetType().FullName)));
}
}
else
{
//创建获取操作上下文对象
context = new MemberGettingContext(owner, members[i], context);
//执行获取操作
owner = getter(context);
if (owner == null)
{
throw new InvalidOperationException($"The result of getter is null.");
}
}
}
if (setter == null)
{
SetMemberValueCore(owner, members[members.Length - 1], valueFactory, true);
}
else
{
setter(new MemberSettingContext <T>(owner, members[members.Length - 1], valueFactory, context));
}
}
internal MemberGettingContext(object owner, MemberToken member, MemberGettingContext parent = null)
{
if(owner == null)
throw new ArgumentNullException(nameof(owner));
if(member == null)
throw new ArgumentNullException(nameof(member));
_owner = owner;
_parent = parent;
_memberToken = member;
}
public static bool TrySetMemberValue <T>(object origin, MemberToken[] members, Func <T> valueFactory, Func <MemberGettingContext, object> getter = null, Action <MemberSettingContext <T> > setter = null)
{
if (origin == null || members == null || valueFactory == null || members.Length == 0)
{
return(false);
}
var owner = origin;
MemberGettingContext context = null;
for (int i = 0; i < members.Length - 1; i++)
{
if (getter == null)
{
if (!TryGetMemberValueCore(owner, members[i], out owner))
{
return(false);
}
}
else
{
//创建获取操作上下文对象
context = new MemberGettingContext(owner, members[i], context);
//执行获取操作
owner = getter(context);
if (owner == null)
{
return(false);
}
}
}
if (setter == null)
{
SetMemberValueCore(owner, members[members.Length - 1], valueFactory, false);
}
else
{
setter(new MemberSettingContext <T>(owner, members[members.Length - 1], valueFactory, context));
}
return(true);
}
internal MemberSettingContext(object owner, MemberToken memberToken, Func <T> valueFactory, MemberGettingContext parent = null) : base(owner, memberToken, parent)
{
if (valueFactory == null)
{
throw new ArgumentNullException(nameof(valueFactory));
}
_valueFactory = valueFactory;
}
internal MemberSettingContext(object owner, MemberToken memberToken, T value, MemberGettingContext parent = null) : base(owner, memberToken, parent)
{
_value = value;
_valueEvaluated = 1;
}
internal MemberGettingContext(object owner, MemberPathSegment memberSegment, MemberGettingContext parent = null)
{
_owner = owner ?? throw new ArgumentNullException(nameof(owner));
_parent = parent;
_memberSegment = memberSegment;
}