Hi all,
I am hoping that someone with some experience developing nTier apps can give
me some advice here.
I am writing an nTier web app that began with a Data Access Layer (DAL),
Business Logic Layer (BLL) and User Interface Layer (UIL).
The problem I found with this was circular referencing...
My objects would be defined in the BLL, so let's say for example that I want
to instantiate a new BLL.Customer object in the UIL, and then run
Customer.AddCus tomer() which would in turn pass the object into the DAL,
let's call this method DAL.AddCustomer (BLL.Customer myCustomer) which would
insert into the DB.
The problem is that the BLL needs to reference the DAL and the DAL needs to
reference the BLL (to receive the custom business object), hence a circular
referencing error. I understand that I could turn this custom object into
some sort of generic object[] or collection and pass it then, or
alternatively pass the method field values one by one (not practical with
10+ values)
What I did was to create a 4th 'vertical' layer which I called the ORL
(Object Reference Layer), the purpose of which is to allow all other layers
to reference the same objects so they can be passed between themselves
without issues. The drawback is that for this to work properly you need to
have the objects themselves defined in the ORL, but the methods defined
statically in the BLL.
My question is this...
Is this good programming?
Obviously it would be ideal to have the object constructor and instance
methods declared in the same class, but I can't seem to get this to work
effectively any other way.
I would appreciate any advice.
- Stu
Nov 17 '05
25  5062 
Hi Steve,
Thanks for the response.
I think your suggestion of writing the DAL as 'stored procedure' wrappers
that accept a simple input, and return a dataset, or datatable is pretty
much what i have aimed to do.
The important thing for me is to be able to pass the actual business object
as a single parameter through to the DAL, and i have achieved this by
creating an Object Reference Layer.
At this point i think i have what i want, the DAL knows nothing about the
BLL but knows where the ORL is, if it's passed a Customer object.
"Steve Walker" <st***@otolith. demon.co.uk> wrote in message
news:W$******** ******@otolith. demon.co.uk...
Typically, a data access tier is meant to encapsulate the access to
persistent storage such that there is no implementation-dependent code
within the BLL. It's often little more than a thin wrapper on a set of
stored procedures. It shouldn't really know anything at all about your
domain model classes.
The problem you've got is where to put the mapping code to connect the
domain model classes to the data access logic. One option is a separate
mapping library which knows about the data access layer, knows about the
domain model, and mediates between them.
http://www.martinfowler.com/eaaCatalog/dataMapper.html
A less clean but simpler solution [simpler for small implementations , I've
found that a mapping-based architecture simplifies large / complex
systems] is to access the DAL directly from within the domain classes. So,
you write a DAL with methods which take simple parameters and return
DataTables and/or DataSets. The code mapping the data to the object is
then encapsulated within the domain model class, which is nice, but knows
a little too much about the underlying storage medium, which is not nice.
--
Steve Walker
Hi Stuart,
Personally, I use strongly-typed datasets as my business objects. I have a
project that only contains the strongly-typed datasets, and both the BLL
project and the DAL project can then reference the datasets project. The
UIL project also references the strongly-typed datasets project, which makes
for easy data binding.
HTH,
Mike Rodriguez
"Stuart Hilditch" <st************ *@gmail.com> wrote in message
news:ID******** *********@news-server.bigpond. net.au... Hi all,
I am hoping that someone with some experience developing nTier apps can
give me some advice here.
I am writing an nTier web app that began with a Data Access Layer (DAL),
Business Logic Layer (BLL) and User Interface Layer (UIL).
The problem I found with this was circular referencing...
My objects would be defined in the BLL, so let's say for example that I
want to instantiate a new BLL.Customer object in the UIL, and then run
Customer.AddCus tomer() which would in turn pass the object into the DAL,
let's call this method DAL.AddCustomer (BLL.Customer myCustomer) which
would insert into the DB.
The problem is that the BLL needs to reference the DAL and the DAL needs
to reference the BLL (to receive the custom business object), hence a
circular referencing error. I understand that I could turn this custom
object into some sort of generic object[] or collection and pass it then,
or alternatively pass the method field values one by one (not practical
with 10+ values)
What I did was to create a 4th 'vertical' layer which I called the ORL
(Object Reference Layer), the purpose of which is to allow all other
layers to reference the same objects so they can be passed between
themselves without issues. The drawback is that for this to work properly
you need to have the objects themselves defined in the ORL, but the
methods defined statically in the BLL.
My question is this...
Is this good programming?
Obviously it would be ideal to have the object constructor and instance
methods declared in the same class, but I can't seem to get this to work
effectively any other way.
I would appreciate any advice.
- Stu
I haven't come across this article yet.
Thanks very much Nigel.
:)
"Nigel Norris" <no****@nospam. com> wrote in message
news:OB******** ******@TK2MSFTN GP09.phx.gbl... Stuart,
Have you read Microsoft's writings on this topic?
"Designing Data Tier Components and Passing Data Through Tiers"
See:
http://msdn.microsoft.com/library/de...tml/boagag.asp
It may leave you more confused, mind you, because it's not entirely clear
in answering your question.
-------
Nigel Norris
"Stuart Hilditch" <st************ *@gmail.com> wrote in message
news:ID******** *********@news-server.bigpond. net.au... Hi all,
I am hoping that someone with some experience developing nTier apps can
give me some advice here.
I am writing an nTier web app that began with a Data Access Layer (DAL),
Business Logic Layer (BLL) and User Interface Layer (UIL).
The problem I found with this was circular referencing...
My objects would be defined in the BLL, so let's say for example that I
want to instantiate a new BLL.Customer object in the UIL, and then run
Customer.AddCus tomer() which would in turn pass the object into the DAL,
let's call this method DAL.AddCustomer (BLL.Customer myCustomer) which
would insert into the DB.
The problem is that the BLL needs to reference the DAL and the DAL needs
to reference the BLL (to receive the custom business object), hence a
circular referencing error. I understand that I could turn this custom
object into some sort of generic object[] or collection and pass it then,
or alternatively pass the method field values one by one (not practical
with 10+ values)
What I did was to create a 4th 'vertical' layer which I called the ORL
(Object Reference Layer), the purpose of which is to allow all other
layers to reference the same objects so they can be passed between
themselves without issues. The drawback is that for this to work properly
you need to have the objects themselves defined in the ORL, but the
methods defined statically in the BLL.
My question is this...
Is this good programming?
Obviously it would be ideal to have the object constructor and instance
methods declared in the same class, but I can't seem to get this to work
effectively any other way.
I would appreciate any advice.
- Stu
Hi Michael,
Sounds like your doing the same thing I am only using datasets rather than
business objects. I would have thought that your application would take a
massive performance by using datasets in this way, especially if you use a
lot of objects. I suppose you can help with caching (if it's an option).
- Stu
"Michael Rodriguez" <mi**@nospamfor me.com> wrote in message
news:OX******** *****@TK2MSFTNG P09.phx.gbl... Hi Stuart,
Personally, I use strongly-typed datasets as my business objects. I have
a project that only contains the strongly-typed datasets, and both the BLL
project and the DAL project can then reference the datasets project. The
UIL project also references the strongly-typed datasets project, which
makes for easy data binding.
HTH,
Mike Rodriguez
"Stuart Hilditch" <st************ *@gmail.com> wrote in message
news:ID******** *********@news-server.bigpond. net.au... Hi all,
I am hoping that someone with some experience developing nTier apps can
give me some advice here.
I am writing an nTier web app that began with a Data Access Layer (DAL),
Business Logic Layer (BLL) and User Interface Layer (UIL).
The problem I found with this was circular referencing...
My objects would be defined in the BLL, so let's say for example that I
want to instantiate a new BLL.Customer object in the UIL, and then run
Customer.AddCus tomer() which would in turn pass the object into the DAL,
let's call this method DAL.AddCustomer (BLL.Customer myCustomer) which
would insert into the DB.
The problem is that the BLL needs to reference the DAL and the DAL needs
to reference the BLL (to receive the custom business object), hence a
circular referencing error. I understand that I could turn this custom
object into some sort of generic object[] or collection and pass it then,
or alternatively pass the method field values one by one (not practical
with 10+ values)
What I did was to create a 4th 'vertical' layer which I called the ORL
(Object Reference Layer), the purpose of which is to allow all other
layers to reference the same objects so they can be passed between
themselves without issues. The drawback is that for this to work properly
you need to have the objects themselves defined in the ORL, but the
methods defined statically in the BLL.
My question is this...
Is this good programming?
Obviously it would be ideal to have the object constructor and instance
methods declared in the same class, but I can't seem to get this to work
effectively any other way.
I would appreciate any advice.
- Stu
Hey,
Just talking from experience, I have achieved the seperation of business
objects (BLL) from database specific calls (DAL) by having mappers that
some of the people talked about.
You can read my comments about the design of my blog which currently can
run on MySql and Sql Server by going here: http://www.laimisnet.com/default.aspx?entryid=18
.. Anyways, the design fit my needs, and I can add another storage
mechanism without modifying bll.
Very interesting reading Laimis.
I am curious, is the mapper implemented as a seperate project in the
solution?
Obviously this is a very good solution for anyone wanting a great deal of
flexibility in which data store is used.
"laimis" <si*****@iit.ed u> wrote in message
news:O1******** *****@TK2MSFTNG P09.phx.gbl... Hey,
Just talking from experience, I have achieved the seperation of business
objects (BLL) from database specific calls (DAL) by having mappers that
some of the people talked about.
You can read my comments about the design of my blog which currently can
run on MySql and Sql Server by going here:
http://www.laimisnet.com/default.aspx?entryid=18
. Anyways, the design fit my needs, and I can add another storage
mechanism without modifying bll.
Stuart Hilditch wrote: Hi all,
I am hoping that someone with some experience developing nTier apps can give
me some advice here.
I am writing an nTier web app that began with a Data Access Layer (DAL),
Business Logic Layer (BLL) and User Interface Layer (UIL).
The problem I found with this was circular referencing...
My objects would be defined in the BLL, so let's say for example that I want
to instantiate a new BLL.Customer object in the UIL, and then run
Customer.AddCus tomer() which would in turn pass the object into the DAL,
let's call this method DAL.AddCustomer (BLL.Customer myCustomer) which would
insert into the DB.
The problem is that the BLL needs to reference the DAL and the DAL needs to
reference the BLL (to receive the custom business object), hence a circular
referencing error. I understand that I could turn this custom object into
some sort of generic object[] or collection and pass it then, or
alternatively pass the method field values one by one (not practical with
10+ values)
What I did was to create a 4th 'vertical' layer which I called the ORL
(Object Reference Layer), the purpose of which is to allow all other layers
to reference the same objects so they can be passed between themselves
without issues. The drawback is that for this to work properly you need to
have the objects themselves defined in the ORL, but the methods defined
statically in the BLL.
My question is this...
Is this good programming?
Obviously it would be ideal to have the object constructor and instance
methods declared in the same class, but I can't seem to get this to work
effectively any other way.
I would appreciate any advice.
- Stu
Google Dependency Inversion Principle and Interface Segregation Principle.
I am by no means an expert but..
In the past I have created another assembly containing an interface that
both the DAL and BLL know about.
This interface pretty much only contains properties for all the db table
columns.
Thus, the DAL classes know about the interface and can interact with
that and the BLL classes implement this interface.
HTH
JB
I did originally use interfaces in the DAL, but it resulted in so much messy
code (some of my object have 25+ properties) I decided that it was far
cleaner to simply reference the object from the ORL.
- Stu
"John B" <jb******@yahoo .com> wrote in message
news:42******** *************** @news.sunsite.d k... Stuart Hilditch wrote: Hi all,
I am hoping that someone with some experience developing nTier apps can
give me some advice here.
I am writing an nTier web app that began with a Data Access Layer (DAL),
Business Logic Layer (BLL) and User Interface Layer (UIL).
The problem I found with this was circular referencing...
My objects would be defined in the BLL, so let's say for example that I
want to instantiate a new BLL.Customer object in the UIL, and then run
Customer.AddCus tomer() which would in turn pass the object into the DAL,
let's call this method DAL.AddCustomer (BLL.Customer myCustomer) which
would insert into the DB.
The problem is that the BLL needs to reference the DAL and the DAL needs
to reference the BLL (to receive the custom business object), hence a
circular referencing error. I understand that I could turn this custom
object into some sort of generic object[] or collection and pass it then,
or alternatively pass the method field values one by one (not practical
with 10+ values)
What I did was to create a 4th 'vertical' layer which I called the ORL
(Object Reference Layer), the purpose of which is to allow all other
layers to reference the same objects so they can be passed between
themselves without issues. The drawback is that for this to work properly
you need to have the objects themselves defined in the ORL, but the
methods defined statically in the BLL.
My question is this...
Is this good programming?
Obviously it would be ideal to have the object constructor and instance
methods declared in the same class, but I can't seem to get this to work
effectively any other way.
I would appreciate any advice.
- Stu
Google Dependency Inversion Principle and Interface Segregation Principle.
I am by no means an expert but..
In the past I have created another assembly containing an interface that
both the DAL and BLL know about.
This interface pretty much only contains properties for all the db table
columns.
Thus, the DAL classes know about the interface and can interact with that
and the BLL classes implement this interface.
HTH
JB
Stuart,
One thing you haven't given any indication of is the scale or requirements
for the project. In practice I think that the appropriate answer to tackling
this sort of problem depends on answers to questions such as:
- How big a project is this?
- How important is flexibility in future?
- Do you need ot have the DAL as a full blown tier (distributable) or is it
simply an internal software layer?
- What is your testing approach - does the DAL need to be replaceable for
testing?
I'd probably come up with very different answers for a 100 user one-off
project than for something that was going to be the key business application
for the next decade. I think all projects should have some sort of
'complexity budget' - where complexity in this case is measured as the ratio
of 'infrastructure ' code to useful application logic. As you add structure
(to reduce complexity in your application logic) you add complexity in extra
code. So it's a tradeoff of whether the benefit outweighs the cost.
So for a really simple project where the DAL was an internal layer I might
just break the layering rule and have the DAL create my busness objects. I'd
keep some separation between the database logic and the 'mapping' component,
per laimis's ideas, but I wouldn't worry too much about making it perfect.
Personally I'd prefer this 'impure' layering to having to have all my
business logic in static methods - that's too high a price to pay. I want to
have my business objects enapsulate data and behaviour, not separate them
out for artificial reasons.
If you want to stick to strict layering, there are two basic approaches:
- pass the data between layers in some simple shared structure, and copy in
the BL to the business objects
- use some form of inversion of control or factory class to pass the
necessary logic into the DAL to allow it to create business objects without
knowing about them
In the first case, use DataSets or custom-defined Data Transfer Objects.
This works well for remoting, as well.
The inversion of control solutions generally seem too complex for me - if
it's getting that complex then I'd be thinking of a full blown O/R mapper
instead of a DAL. However one simple variation that I've considered but not
used in practice is to use strongly typed datasets as the basis for the
business objects in the BL and pass in datasets to the DAL. In the style
'here's a dataset - please fill it for me'. The DAL works against simple
untyped dataset interfaces, but the dataset insfrastructure creates the
approriate strongly typed objects.
Good luck..
Nigel
"Stuart Hilditch" <st************ *@gmail.com> wrote in message
news:FJ******** **********@news-server.bigpond. net.au... I did originally use interfaces in the DAL, but it resulted in so much
messy code (some of my object have 25+ properties) I decided that it was
far cleaner to simply reference the object from the ORL.
- Stu
"John B" <jb******@yahoo .com> wrote in message
news:42******** *************** @news.sunsite.d k... Stuart Hilditch wrote: Hi all,
I am hoping that someone with some experience developing nTier apps can
give me some advice here.
I am writing an nTier web app that began with a Data Access Layer (DAL),
Business Logic Layer (BLL) and User Interface Layer (UIL).
The problem I found with this was circular referencing...
My objects would be defined in the BLL, so let's say for example that I
want to instantiate a new BLL.Customer object in the UIL, and then run
Customer.AddCus tomer() which would in turn pass the object into the DAL,
let's call this method DAL.AddCustomer (BLL.Customer myCustomer) which
would insert into the DB.
The problem is that the BLL needs to reference the DAL and the DAL needs
to reference the BLL (to receive the custom business object), hence a
circular referencing error. I understand that I could turn this custom
object into some sort of generic object[] or collection and pass it
then, or alternatively pass the method field values one by one (not
practical with 10+ values)
What I did was to create a 4th 'vertical' layer which I called the ORL
(Object Reference Layer), the purpose of which is to allow all other
layers to reference the same objects so they can be passed between
themselves without issues. The drawback is that for this to work
properly you need to have the objects themselves defined in the ORL, but
the methods defined statically in the BLL.
My question is this...
Is this good programming?
Obviously it would be ideal to have the object constructor and instance
methods declared in the same class, but I can't seem to get this to work
effectively any other way.
I would appreciate any advice.
- Stu
Google Dependency Inversion Principle and Interface Segregation
Principle.
I am by no means an expert but..
In the past I have created another assembly containing an interface that
both the DAL and BLL know about.
This interface pretty much only contains properties for all the db table
columns.
Thus, the DAL classes know about the interface and can interact with that
and the BLL classes implement this interface.
HTH
JB
Thanks very much Nigel,
That's great feedback and it's given me something to think about. I do agree
that being limited to static methods only is a price to pay, I think i might
start looking into to transferring these objects from the BLL to the DAL by
way of a dataset, it sounds like a practical option.
Thanks again!
"Nigel Norris" <no****@nospam. com> wrote in message
news:OY******** ******@TK2MSFTN GP09.phx.gbl... Stuart,
One thing you haven't given any indication of is the scale or requirements
for the project. In practice I think that the appropriate answer to
tackling this sort of problem depends on answers to questions such as:
- How big a project is this?
- How important is flexibility in future?
- Do you need ot have the DAL as a full blown tier (distributable) or is
it simply an internal software layer?
- What is your testing approach - does the DAL need to be replaceable for
testing?
I'd probably come up with very different answers for a 100 user one-off
project than for something that was going to be the key business
application for the next decade. I think all projects should have some
sort of 'complexity budget' - where complexity in this case is measured as
the ratio of 'infrastructure ' code to useful application logic. As you add
structure (to reduce complexity in your application logic) you add
complexity in extra code. So it's a tradeoff of whether the benefit
outweighs the cost.
So for a really simple project where the DAL was an internal layer I might
just break the layering rule and have the DAL create my busness objects.
I'd keep some separation between the database logic and the 'mapping'
component, per laimis's ideas, but I wouldn't worry too much about making
it perfect.
Personally I'd prefer this 'impure' layering to having to have all my
business logic in static methods - that's too high a price to pay. I want
to have my business objects enapsulate data and behaviour, not separate
them out for artificial reasons.
If you want to stick to strict layering, there are two basic approaches:
- pass the data between layers in some simple shared structure, and copy
in the BL to the business objects
- use some form of inversion of control or factory class to pass the
necessary logic into the DAL to allow it to create business objects
without knowing about them
In the first case, use DataSets or custom-defined Data Transfer Objects.
This works well for remoting, as well.
The inversion of control solutions generally seem too complex for me - if
it's getting that complex then I'd be thinking of a full blown O/R mapper
instead of a DAL. However one simple variation that I've considered but
not used in practice is to use strongly typed datasets as the basis for
the business objects in the BL and pass in datasets to the DAL. In the
style 'here's a dataset - please fill it for me'. The DAL works against
simple untyped dataset interfaces, but the dataset insfrastructure creates
the approriate strongly typed objects.
Good luck..
Nigel
"Stuart Hilditch" <st************ *@gmail.com> wrote in message
news:FJ******** **********@news-server.bigpond. net.au...I did originally use interfaces in the DAL, but it resulted in so much
messy code (some of my object have 25+ properties) I decided that it was
far cleaner to simply reference the object from the ORL.
- Stu
"John B" <jb******@yahoo .com> wrote in message
news:42******** *************** @news.sunsite.d k... Stuart Hilditch wrote:
Hi all,
I am hoping that someone with some experience developing nTier apps can
give me some advice here.
I am writing an nTier web app that began with a Data Access Layer
(DAL), Business Logic Layer (BLL) and User Interface Layer (UIL).
The problem I found with this was circular referencing...
My objects would be defined in the BLL, so let's say for example that I
want to instantiate a new BLL.Customer object in the UIL, and then run
Customer.AddCus tomer() which would in turn pass the object into the
DAL, let's call this method DAL.AddCustomer (BLL.Customer myCustomer)
which would insert into the DB.
The problem is that the BLL needs to reference the DAL and the DAL
needs to reference the BLL (to receive the custom business object),
hence a circular referencing error. I understand that I could turn this
custom object into some sort of generic object[] or collection and pass
it then, or alternatively pass the method field values one by one (not
practical with 10+ values)
What I did was to create a 4th 'vertical' layer which I called the ORL
(Object Reference Layer), the purpose of which is to allow all other
layers to reference the same objects so they can be passed between
themselves without issues. The drawback is that for this to work
properly you need to have the objects themselves defined in the ORL,
but the methods defined statically in the BLL.
My question is this...
Is this good programming?
Obviously it would be ideal to have the object constructor and instance
methods declared in the same class, but I can't seem to get this to
work effectively any other way.
I would appreciate any advice.
- Stu
Google Dependency Inversion Principle and Interface Segregation
Principle.
I am by no means an expert but..
In the past I have created another assembly containing an interface that
both the DAL and BLL know about.
This interface pretty much only contains properties for all the db table
columns.
Thus, the DAL classes know about the interface and can interact with
that and the BLL classes implement this interface.
HTH
JB
This thread has been closed and replies have been disabled. Please start a new discussion. Similar topics | |
by: Arsen Vladimirskiy |
last post by:
Hello,
If I have a few simple classes to represent Entities such as Customers and
Orders.
What is the proper way to pass information to the Data Access Layer?
1) Pass the actual ENTITY to the Data Access Layer method
-or-
2) Pass some kind of a unique id to the Data Access Layer method
|
by: Simon Harvey |
last post by:
Hi,
In my application I get lots of different sorts of information from
databases. As such, a lot of information is stored in DataSets and DataTable
objects.
Up until now, I have been passing around chunks of data in
DataTables/DataSets, simply because that was the format that they were in
when the data was taken from the database. Now, I know this maybe a pretty
silly question with a standard "it depends" answer, but I'm going to...
|
by: Jack |
last post by:
Hi,
I have a hashtable that I need to pass around to different Business Objects.
My question is it better to pass it and make a locale hashtable variable and
set it equal to the passed hashtable or should I pass it and not worry about
it?
Thanks
|
by: Marc Castrechini |
last post by:
First off this is a great reference for passing data between the Data Access
and Business Layers:
http://msdn.microsoft.com/library/default.asp?url=/library/en-us/dnanchor/html/Anch_EntDevAppArchPatPrac.asp
I use my own classes in the Business layer. I want to keep the Data Access
layer from requiring these classes so I tried passing a Datarow between the
layers and it seems to work good for me. Constructing the datarow in the
Class...
|
by: Noel |
last post by:
Hello,
I'm currently developing a web service that retrieves data from an employee
table. I would like to send and retrieve a custom employee class to/from the
webservice. I have currently coded the custom employee class and have built
it as a separate library (employee.dll). This employee.dll is being
referenced by both the web service and the windows application.
I face the following problem when I send this class to the webservice.
| | |
by: Peter M. |
last post by:
Hi all,
I'm currently designing an n-tier application and have some doubts about my
design.
I have created a Data Access layer which connects to the database (SQL
Server) and performs Select, update, delete and inserts. I use dataset
objects to pass data to and from the DAL.
In my GUI (windows forms), I use databinding to bind controls to a datatable
|
by: waheed azad |
last post by:
Hi,
I have a been developing an accounting system for a non-profit organization. I had decided to to divide the solution, in three layers, presentation, business layer and database layer.
My business layer is composed of objects like Account, Transaction, Voucher etc. And my database layer is composed of objects like AccountDB, TransactionDB, VoucherDB.
Now each of my layer is residing in a seperate project under the same solution....
|
by: grawsha2000 |
last post by:
Greetings,
I am developing this N-tier business app. The problem I'm facing is
when I try to pass business objects (employees, dept..etc) from
business tier to data tier,i.e., the add method in the data tier
expects business object from the business tier, I get an error saying:
Can not covert businesslayer.emp to businesslayer.emp
|
by: Andrus |
last post by:
Winforms UI assembly has static FormManager.FormCreator method which creates
forms taking entity as parameter.
I need to pass this method to business objects in business assembly so that
business methods can also create
forms but does not have reference to UI assembly.
I tried code below but got compile errows shown in comments.
How to fix ?
Andrus.
|
by: marktang |
last post by:
ONU (Optical Network Unit) is one of the key components for providing high-speed Internet services. Its primary function is to act as an endpoint device located at the user's premises. However, people are often confused as to whether an ONU can Work As a Router. In this blog post, we’ll explore What is ONU, What Is Router, ONU & Router’s main usage, and What is the difference between ONU and Router. Let’s take a closer look !
Part I. Meaning of...
|
by: Oralloy |
last post by:
Hello folks,
I am unable to find appropriate documentation on the type promotion of bit-fields when using the generalised comparison operator "<=>".
The problem is that using the GNU compilers, it seems that the internal comparison operator "<=>" tries to promote arguments from unsigned to signed.
This is as boiled down as I can make it.
Here is my compilation command:
g++-12 -std=c++20 -Wnarrowing bit_field.cpp
Here is the code in...
| | |
by: jinu1996 |
last post by:
In today's digital age, having a compelling online presence is paramount for businesses aiming to thrive in a competitive landscape. At the heart of this digital strategy lies an intricately woven tapestry of website design and digital marketing. It's not merely about having a website; it's about crafting an immersive digital experience that captivates audiences and drives business growth.
The Art of Business Website Design
Your website is...
|
by: Hystou |
last post by:
Overview:
Windows 11 and 10 have less user interface control over operating system update behaviour than previous versions of Windows. In Windows 11 and 10, there is no way to turn off the Windows Update option using the Control Panel or Settings app; it automatically checks for updates and installs any it finds, whether you like it or not. For most users, this new feature is actually very convenient. If you want to control the update process,...
|
by: tracyyun |
last post by:
Dear forum friends,
With the development of smart home technology, a variety of wireless communication protocols have appeared on the market, such as Zigbee, Z-Wave, Wi-Fi, Bluetooth, etc. Each protocol has its own unique characteristics and advantages, but as a user who is planning to build a smart home system, I am a bit confused by the choice of these technologies. I'm particularly interested in Zigbee because I've heard it does some...
|
by: isladogs |
last post by:
The next Access Europe User Group meeting will be on Wednesday 1 May 2024 starting at 18:00 UK time (6PM UTC+1) and finishing by 19:30 (7.30PM).
In this session, we are pleased to welcome a new presenter, Adolph Dupré who will be discussing some powerful techniques for using class modules.
He will explain when you may want to use classes instead of User Defined Types (UDT). For example, to manage the data in unbound forms.
Adolph will...
|
by: conductexam |
last post by:
I have .net C# application in which I am extracting data from word file and save it in database particularly. To store word all data as it is I am converting the whole word file firstly in HTML and then checking html paragraph one by one.
At the time of converting from word file to html my equations which are in the word document file was convert into image.
Globals.ThisAddIn.Application.ActiveDocument.Select();...
|
by: TSSRALBI |
last post by:
Hello
I'm a network technician in training and I need your help.
I am currently learning how to create and manage the different types of VPNs and I have a question about LAN-to-LAN VPNs.
The last exercise I practiced was to create a LAN-to-LAN VPN between two Pfsense firewalls, by using IPSEC protocols.
I succeeded, with both firewalls in the same network. But I'm wondering if it's possible to do the same thing, with 2 Pfsense firewalls...
| | |
by: 6302768590 |
last post by:
Hai team
i want code for transfer the data from one system to another through IP address by using C# our system has to for every 5mins then we have to update the data what the data is updated we have to send another system
| |
