WriteOnly

[elektrowolf]

Alpha Nerd wrote:

Who would use it? A coding horror in VB.

In VB? In C#, too: class Foo { private int _val; public int Val { set { this._val = value; } } }

[Dr Walt Fair PE]

The best use for write-only things, in general, is when you are dealing with real-time control interfaces. Some devices allow you to save data to a memory location or port and that sets control bits in an external device. As far as the external device is concerned, it is an input-only deal; from the program's viewpoint it's write-only and any attempt to read would be undefined or return garbage. One logical use for a write-only property would be to control interfaces with external hardware. You would define a class encapsulating the hardware access and anything that writes to the hardware without any chance of being able to read the real-time results back, would logically be marked as WriteOnly. This is fairly common when using some PIC chips, DSP chips and assorted other devices. In my DSP applications, marking output data as WriteOnly would make perfect sense, since once it is sent to the buffer, it goes out the sound interface and does not exist anywhere that is accessible to the software. (Note: I haven't done that, since I knew it was essentially write-only and never thought I might try to read it again.) To me, marking a property as WriteOnly in a VB, C, C# or any other language very clearly tells everyone not to even bother to read it back because the data no longer exists. Another use for WriteOnly properties would be when dealing with highly asychronous processes, but I won't go into that here. So, yeah, if you're dealing with stuff in your own application's memory, WriteOnly may not make much sense, but if you are dealing with control systems and external devices, it may well make perfect sense.

The PetroNerd

Walt Fair, Jr. Comport Computing Specializing in Technical Engineering Software

[Dave Kreskowiak]

I think the light is processed into something else. I couldn't tell what though, because, like, there's no light! :-D

A guide to posting questions on CodeProject[^]
Dave Kreskowiak Microsoft MVP Visual Developer - Visual Basic
     2006, 2007, 2008

[Luc Pattyn]

Aha, I see. Or actually maybe I don't, lacking some light??

Luc Pattyn [Forum Guidelines] [My Articles]

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[PIEBALDconsult]

I suppose a write-only property (in whatever language, but preferably C#) could be used when defining something like a queue (Enqueue) or a stack (Push). (Though not recommended.)

[elektrowolf]

Full ACK. It's those little advantages of C# like anonymous delegates, lambda expressions without return value, automatic properties, a.s.o. that made me prefer C#. But one can't say VB is horrible! Basically, it has all features of C# and just an other syntax.

[Russell Jones]

writeonly properties are just as possible in c#, just create a property without an accessor. It's probably not great practice to use one but there may be times when it came in handy

[Lost User]

I quite often use write only properties in C# Consider this: Object A depends on an internal state and also needs an Object B for whatever it does. Object B inherits from a baseclass or interface, so there are many classes that may be used to create an instance to use as object B. Hardcoding it in A is not an option. Instead I use a write only property of A to pass a suitable object B at runtime. Object A then reinitializes it's internal state and prepares B for its use. I do not want to have access to object B anymore. It is not needed and indeed any tampering with B would have a bearing on A's state. With a write only property this problem cannot arise.

[Mr PoorEnglish]

MarkBrock wrote:

VB itself is a coding horror.

maybe the greatest advantage to VB is that the programmers aren't as arrogant as C# programmers. (otherwise: the meaning of writeonly also is a secret for me.)

[MarkB777]

haha I don't think any of the "anti-VB"'ers in here are really serious about what they say. I've worked on a very large VB.NET project as well - A customized CMS for our government. People are just taking the piss. ;)

Mark Brock Click here to view my blog

[Lost User]

Arrogance? Perhaps, but stereotypes usually do not come out of a void. Until .Net VB hardly was a candidate to do any serious work with. And those who tried often gave a picture of needlessly fighting windmills to overcome its shortcomings and proove that they were right. Also, the acronym 'BASIC' is still held high by advertising VB as the ideal language for beginners. Is it really a wonder that all diehard VB users are automatically percieved as such? Last, the syntax obviously is one of those love-or-hate things. So am I being arrogant if I don't want to be irritated by it the entire day? Or am I arrogant when I decide that I have better things to do than arguing with people who automatically put me into the 'annoying newbie' box?

[Mr PoorEnglish]

CDP1802 wrote:

but stereotypes usually do not come out of a void.

That may be right, but then its a question of character, whether you want to take stereotypes for your opinion, and wether you want to reproduce stereotypes on and on. To have preferences cannot be called arrogance, neither criticizing some VB concepts. (I've lots of criticism myself, for example the mixing up of "=" and "==" in one operator - gruesome, isn't it?) But to me it's the IDE, which keeps me staying in VB, because of the background-compiling, because contextmenu "go to definition" leads directly to the objectbrowser, and the objectbrowser displays the return-types of functions already in the overview.

[VentsyV]

MarkBrock wrote:

I've worked on a very large VB.NET project as well - A customized CMS for our government.

Not the one for the FBI that failed miserably and waisted $100 mil taxpayer's money by any chance is it ?

[MarkB777]

haha... that's classified :).

Mark Brock Click here to view my blog

[Jorgen Sigvardsson]

Member 2411327 wrote:

The two main diferences i noticed on the transition was that intelisence is a lot better on VB, and on vb i don't have to compile the code to see errors.

That's not a language difference, it's an IDE difference.

-- Kein Mitleid Für Die Mehrheit

[Jonathan C Dickinson]

I am a 8yr VB (and generic BASIC) refugee and I must say that C# has given me a warm fuzzy feeling since I started using it. One word: keystrokes ;).