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hi, 
what is the advantages of switch over the if/else ?
where we prefer the if/else over the switch?
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Switches are generally easer to read for a large number of conditions or a set of conditions that could possibly change over the lifetime of the product. If/else is great when you have a small (2-3, in my opinion) number of conditions.
That being said, there are times when you still have to use an if/else (or if/else if/else) block with a large number of conditions as switches only let you switch on a limited set of data types.
Scott Dorman Microsoft® MVP - Visual C# | MCPD
President - Tampa Bay IASA
[ Blog][ Articles][ Forum Guidelines]
Hey, hey, hey. Don't be mean. We don't have to be mean because, remember, no matter where you go, there you are. - Buckaroo Banzai
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In addition to the above, with some data, a switch statement will resolve into a simple jump table. A switch statement with strings may end up using a hash table, increasing performance.
Even for simple compares, I tend to use if/else if the number of elements is one or two items.
Anyone who thinks he has a better idea of what's good for people than people do is a swine.
- P.J. O'Rourke
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Anywhere you compare the same expression to several values, you can use a switch instead.
If you have a lot of comparisons, a switch usually gives clearer code, and may perform a bit better. If you only have two-three comparisons, it's mostly a matter of taste. Use whatever best fits the intention of the code.
Despite everything, the person most likely to be fooling you next is yourself.
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Guffa wrote: Anywhere you compare the same expression to several values, you can use a switch instead.
As long as they are simple integers, or strings; and literal!
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If you have a very large number of possible values to test for, you can order nested if/else structures to simulate a binary search.
For the innermost loop of time-critical code, this can run faster than a switch that tests each value sequentially.
For example if value is between 0 and 7:
if (value < 4)
if (value < 2)
if (value == 0)
else
else
if (value == 2)
else
else
This will find the value in three steps, as opposed to up to seven steps using a sequential method.
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Don't forget that a switch allows you to have a code block that matches several values.
And a goto case isn't quite as maligned at a raw goto.
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Hello everyone,
New to Web Services. After some experiment, some basic questions.
1. What is the function of a code hehind file? Any benefits of have a separate asmx and asmx.cs file?
2. When we press F5 to debug, I it is not running on IIS. If IIS is not hosting the web services, which party hosts the web services when we use F5 to debug?
3. I am always confused what is the function and why we need [WebService]? I think [WebMethod] is enough since we expose web service through a public function, not through a class (marked with WebService attribute).
thanks in advance,
George
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George_George wrote: 1. What is the function of a code hehind file? Any benefits of have a separate asmx and asmx.cs file?
The code behind file allows you to separate the code from the presentation (UI). You generally want to do this so you can make changes to the logic without affecting the UI and/or allow a graphics designer to work with the UI and not affect the logic.
George_George wrote: 2. When we press F5 to debug, I it is not running on IIS. If IIS is not hosting the web services, which party hosts the web services when we use F5 to debug?
I'm not 100% sure on this, but I believe it will be running on an internal web service that is started by Visual Studio.
George_George wrote: 3. I am always confused what is the function and why we need [WebService]? I think [WebMethod] is enough since we expose web service through a public function, not through a class (marked with WebService attribute).
From MSDN[^]: The WebServiceAttribute is not required for an XML Web service to be published and executed. You can use the WebServiceAttribute to specify a name for the XML Web service that is not restricted by the rules for a common language runtime identifier, which is used in the service description and the Service help page for the XML Web service.
An XML Web service should change its default XML namespace before it is made public. Each XML Web service needs a unique XML namespace to identify it so that client applications can distinguish it from other services on the Web. http://tempuri.org/ is available for XML Web services that are under development, but published XML Web services should use a more permanent namespace.
Scott Dorman Microsoft® MVP - Visual C# | MCPD
President - Tampa Bay IASA
[ Blog][ Articles][ Forum Guidelines]
Hey, hey, hey. Don't be mean. We don't have to be mean because, remember, no matter where you go, there you are. - Buckaroo Banzai
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Thanks Scott,
1.
For UI, I am confused. Web Service has no UI, right? What do you mean UI here? Graphical User Interface?
2.
For item 3.
In my previous senses, I think a web serivce is a remote method call which takes some parameters and return something, so I think it is similar to a method, so I think a public method described with WebMethod is called a web service. This is why I am confused and asked question 3.
And from your experience, you call a class a web service? If the class has more than one Web Methods, how do you call the methods?
regards,
George
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George_George wrote: For UI, I am confused. Web Service has no UI, right? What do you mean UI here? Graphical User Interface?
Ahhh...yes, web serivces have no UI. (Yes, UI == Graphical User Interface.) However, my statement about the purpose of a code behind (in general) still holds true. The asmx is the service equivalent to the aspx file. Best practice should still be to put the code in the code behind file.
George_George wrote: In my previous senses, I think a web serivce is a remote method call which takes some parameters and return something, so I think it is similar to a method, so I think a public method described with WebMethod is called a web service. This is why I am confused and asked question 3.
You are almost correct. A web service method is a remote method call which takes some parameters and return something. A web service is a collection of web service methods.
George_George wrote: And from your experience, you call a class a web service? If the class has more than one Web Methods, how do you call the methods?
Yes, a class would be called a web service. If it has more than one web method, you still call them the same way as if it only had a single web method.
Scott Dorman Microsoft® MVP - Visual C# | MCPD
President - Tampa Bay IASA
[ Blog][ Articles][ Forum Guidelines]
Hey, hey, hey. Don't be mean. We don't have to be mean because, remember, no matter where you go, there you are. - Buckaroo Banzai
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Cool Scott!
Yes, we always edit asmx.cs file for implementation for detailed logics for web services. But what the benefit or benefits will we have if we separate a couple of lines of XML document in asmx and source codes in asmx.cs file? Could you show me a sample to show the benefits please?
regards,
George
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Can't really show any concrete (or probably even any abstract) examples that show the benefits for web services. Anything else, I think the benefits are trivially clear (separation of concerns is almost always a good thing).
Scott Dorman Microsoft® MVP - Visual C# | MCPD
President - Tampa Bay IASA
[ Blog][ Articles][ Forum Guidelines]
Hey, hey, hey. Don't be mean. We don't have to be mean because, remember, no matter where you go, there you are. - Buckaroo Banzai
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Thanks Scott,
I understand the general point of design separation (or loosely coupled), but what specific points do you mean separation here?
regards,
George
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George_George wrote: but what specific points do you mean separation here?
I'm not sure I can give you specifics. If you already understand the benefits of separating the UI logic from the back-end logic, you have what you need. As I said, there are probably less reasons for doing this in a web service other than following best practices and making maintenance a bit easier.
Scott Dorman Microsoft® MVP - Visual C# | MCPD
President - Tampa Bay IASA
[ Blog][ Articles][ Forum Guidelines]
Hey, hey, hey. Don't be mean. We don't have to be mean because, remember, no matter where you go, there you are. - Buckaroo Banzai
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Thanks Scott,
I basic agree with you. But do not agree with your term UI. The asmx file (not asmx.cs) contains only XML mark-up language and real logic/UI (e.g. Web Forms controls) are in asmx.cs file.
Any comments?
regards,
George
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Yes, an asmx file should contain only the XML markup. As I said, in the case of a web service, there really is no UI so the separation of concerns isn't nearly as noticeable.
Scott Dorman Microsoft® MVP - Visual C# | MCPD
President - Tampa Bay IASA
[ Blog][ Articles][ Forum Guidelines]
Hey, hey, hey. Don't be mean. We don't have to be mean because, remember, no matter where you go, there you are. - Buckaroo Banzai
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Thanks Scott,
So the purpose is just to separate the markup language logics asmx file from real C# implementation code in asmx.cs file?
regards,
George
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Yes.
Scott Dorman Microsoft® MVP - Visual C# | MCPD
President - Tampa Bay IASA
[ Blog][ Articles][ Forum Guidelines]
Hey, hey, hey. Don't be mean. We don't have to be mean because, remember, no matter where you go, there you are. - Buckaroo Banzai
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Cool, Scott!
regards,
George
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George_George wrote: Could you show me a sample to show the benefits please?
It's basically separation of markup and code. I believe there won't be any other reason.
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Thanks N a v a n e e t h. Mark up you mean the XML line in asmx?
regards,
George
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Hello,
Is there any other way to send mails from .net without using the SMTP server.If there is an exchange server in the organization should all clients have to connect to its smtp server or there is another way.
Thanks.
Dad
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Hello all,
I need some help on an issue i do have.
My problem is rather simple.
I have created a project (that would be the server) and that is supposed to perform some lengthy calculations. This server would be located on a machine dedicated to calculations.
On the other hand, I have created a client (my GUI) that will be located on another computer and that will send data/parameteres to the server, wait for the server to calculate based on the parameters received, and send back the result of the calculation to the GUI (my client). In my case, results would be displayed in a DataGridView for example.
So my question is rather simple: How do I make the client and server communicate, namely how do I send data (could be aything from a string to a double to a bolean) to the server, and most of all how do I retrieve data calculated for display in my GUI ?
This issue is related to some Finance application and real time data. Calculations are perfromed on the server as well as retrieving the real time data, and send back to the client for vizualisation ! GUI is sending the parameteres on which calculation are based.
I understand I have to use net.sockets, and create some kindof remotable objects in the middle to transfer information, but I can't figure out how to do this after reading some of the very useful articles here.
Any help would be really appreciated !
Thank you
C
modified on Saturday, July 12, 2008 11:40 PM
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Hi All,
I put a rich text box in my app and then code the listener of the box to listen for emoticon text ie ); etc and replace with the emoticon? If i have to do this, then how do I add an emoticon .gif file into the Rich text box?
Is there any other easier and free way of doing this, like plugins etc?Thanks In Advance.
SHINOJ K
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