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I have developed several n-tier web apps:
* business logic layer
* DALC
* presentation layer
As I understand, a Business Facade layer can go on top of the business logic layer - basically as an additional layer of abstraction. Is this correct?
How many projects have you worked on where you've used a Business Facade layer? What are the main variations of this architecture? What are the pros and cons of this architecture?
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I think a more common layer is a Service Layer. Your domain (business logic) should be isolated from other layers. The first layer of isolation is the Data Access Layer, which abstracts your domain from the data store. The second layer of isolation is usually a Service Layer, or sometimes called the Application Layer. This layer is intended to isolate your domain from its consumers, presenting a simpler API to the world of consumers (presentation, other businesses, other departments, etc.) Some consider services to be part of the domain, and thats certainly a valid opinnion. The main goal is to provide a contract that the products that need to consume your domain can bind to, rather than binding directly to all the various business objects in your domain. This allows your domain and the consumers of it to vary as needed, without having broad repercussions when the domain needs to change in the face of changing business requirements.
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Isn't a "Business Service Layer" the same thing as a "Service Facade"?
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Not really. Services do provide a "facade", where a facade is a simplified API to a complex subsystem. However, services conform to a more strict set of rules, and are intended to be THE API, not a simplified API. Unlike a simple facade layer, which is just a simplification layer, the services in a service layer should conform to the following principles:
- formal contract
- loose coupling
- abstraction
- reusability
- autonomy
- statelessness
- discoverability
- composability
Conforming to those principles will maximize the long term maintainability of your project, keep layers loosly coupled, etc.
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This is (possibly) just a quick one. I have a website set up with 3 roles, i want a user to be able to choose between 2 of these when registering (A and B for example), the third is the admin role. Is there anyways of adding this as a drop down list/radio button on the asp:creatuserwizard6
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Hi all,
I am creating a type of control that is used to display fill-in-blank questions, the control will have a drop down list in the location of each blank with 4 options to choose from, like this
The elephant [is, are, us, we] a very big Mammal that [eat, eating, eats, ate] plants...
[is, are, us, we] = drop down list with 4 options that the student uses to choose the best answer.
The question is how to dynamically create drop down server controls AND position them in the correct place within the words of the paragraph?
Any ideas?
Thanks
And ever has it been that love knows not its own depth until the hour of separation
Mohammad Gdeisat
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hi,i want to create graphs...plz help me..
txs in advance...
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If you are working on .NET 3.5,Then You can sue Microsoft Chart Control. Or you can use some third party control like, Dundas Chart
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If your interested in writing your own graphing controls, you should check out the Raphael JavaScript library. Its a common wrapper around the various vector frameworks in different browsers. You can use the simplified Raphael API to create vector graphics that work in IE (VML), FireFox (SVG), Opera/Safari (Canvas), etc.
http://raphaeljs.com/[^]
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Hi,
I am using DataSet as a datasource to my CrystalReport and I have no problem in displaying the data. But there is a column called MoneyWithHeld and I am trying to find a way how to calculate the sum or total of these values. I searched online and have found two possible solutions
1).Using Formula Fields -- Created a field called TotalWithHeld and in the formula I just put Sum({DataSet.MoneyWithHeld}) and that is it but no luck. I am pretty sure I have missed some thing else here but not sure what it was. Becuase while I was trying to save this TotalWithHeld field I ran into some syntax errors and as a result of those while trying to run the report the error was 'The function cannot be used because it must be evaluated later' .
2).Running Total -- I picked my DataSet.MoneyWithHeld filed to 'field to summarize' text box and I picked the "Sum" under type of summary drop down. When I run my app it wouldn't give me any error as it was in the case #1 but it wasn't displaying the total but just the last value of the MoneyWithHeld in the last record. I tried picking the Count, distinct count but nothing has worked. Looks like here too I need to put some kind of formula by selcting the radio button 'use a forumula' but not sure how to put it to get the total.
I am kind of new to this Crystal reports would some one be kind enough to help me with this?
Thanks,
-L
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Hi,
I am summing a column in my DataGrid and displaying total at the
footer with the below piece of code
If e.Item.ItemType = ListItemType.Item Or e.Item.ItemType = ListItemType.AlternatingItem Then
'Snip out the ViewCount
Dim ContributionWithHeld As Integer = Convert.ToInt32(DataBinder.Eval(e.Item.DataItem, "ContributionWithHeld"))
myTotalContributionWithHeld += ContributionWithHeld
ElseIf e.Item.ItemType = ListItemType.Footer Then
e.Item.Cells(20).Text = "Total: " & String.Format("{0:#,###}", myTotalContributionWithHeld)
End If
and it works great and it dispaly the correct total when it binds the
data. But if I click on Edit row button in the grid then the Sum/Total
at the footer changes (deducts the value of that cell in that row from
the total). Looks like the the row that is in Edit mode is not being
taken into acount while summing the values.
Can some one help me with this how to change the above code or what I
else I need to do to display the Sum correct even if any of the rows
in Edit mode.
Also, the other thing I would like to be able to do is when a row in
Edit mode and as I change the value in the Cell that I would like
Sum , the Sum at the footer needs to be changed. May be I need to do
it under OnCellChange event but not sure where and how do I do it as I
never done this before.
Please help.
Thanks,
-L
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HI,
Looks like it also works good as expected when I changed the If statement to include 'Or e.Item.ItemType = ListItemType.EditItem' at the end. So I am good with the Sum/Total now. But when I change the Cell I would like the Total/Sum also be changed. Any help appreciated.
Thanks,
-L
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The following code snippet defines a hotspot which the user can click and where conditions can be created depending on the postback value.
Are there any tools or libraries in order to show the boundaries visually rather than counting the pixels?
<form id="form1" runat="server">
<asp:imagemap id="Imagemap1" runat="server" imageurl="Kids.jpg" xmlns:asp="#unknown">
Width="300" OnClick="Imagemap1_Click" HotSpotMode="PostBack">
<asp:rectanglehotspot top="0" bottom="225" left="0" right="150">
AlternateText="Sofia" PostBackValue="Sofia">
</asp:rectanglehotspot>
<asp:rectanglehotspot top="0" bottom="225" left="151" right="300">
</asp:rectanglehotspot></asp:imagemap></form>
Jon
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Hi friends,
Am creating a blog for the website. In this how can i add extra storage?
For understanding:
If we find ourself running out of space, it’s easy to add more storage to our blog.
we can add 5, 15, or 25 gigabytes to your blog,
So that we can add more pictures, videos to it.
For this what i want to do?
Give some idea
----
Glossy**
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Well, if your users can all add 25 gig, you need some huge hard drives. I'd imagine at the end of the day, it would all be virtual, with all the content stored in a database, and the 'space' equating to a running total of how much DB space they have taken up and therefore how much they have left.
Christian Graus
Driven to the arms of OSX by Vista.
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Hi friends,
How to add water mark text to the search textbox?
Do we want to use ajax for it?
----
Glossy**
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Thank you yogi
----
Glossy**
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Hi friends,
How to add avadar function to Blog in the website.
Am doing it in asp.net 3.5 (C# application)
Give some idea
Thank you
----
Glossy**
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You want to store a users image, and associate it with the user. Then you want an img tag pointing to that image ( probably streaming it from your DB ). Which bit is hard ?
Christian Graus
Driven to the arms of OSX by Vista.
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i have master page, on which i have different hyperlink
in codebehing, how i will access click hyperlink id??
i want current click hyperlink id in codebehind
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If it is link button, then the sender argument would help you with that right?
Vasudevan Deepak Kumar
Personal Homepage Tech Gossips
The woods are lovely, dark and deep,
But I have promises to keep,
And miles to go before I sleep,
And miles to go before I sleep!
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Hi,
There is a label control on .aspx
The text "hello" comes from database i.e.
label1.text = "hello";
Note that, I do not have permission to change the UI code.
I would like to alter the value of the field in the table to show the text as bold i.e.
To have the text displayed as highlighted i.e. bold, I manually modified the text inside the field of the table to show
hello
Is this ok?
It does not seem to work because in the label control I see:
hello
Any thoughts please?
Thanks
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The label renders as a span tag. Did you try manipulating it from JavaScript?
Vasudevan Deepak Kumar
Personal Homepage Tech Gossips
The woods are lovely, dark and deep,
But I have promises to keep,
And miles to go before I sleep,
And miles to go before I sleep!
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