|
OK I'm a database programmer and have no experience with graphic programming.
My boss is wondering if I can read data into an animated display.
Similar to an o-scope. Scrolling value and time base with the data line graph in real time.
Where can I find some info on how to get something like this started??
TIA
Rafone
Statistics are like bikini's...
What they reveal is astonishing ...
But what they hide is vital ...
|
|
|
|
|
The most efficient way should be using a third party control. For example Steema[^] has a graph type FastLine in TeeChart component library.
Another possibility could be Dundas[^].
The need to optimize rises from a bad design.
My articles[ ^]
|
|
|
|
|
Well, it appears as if normal (non administrator) users using Vista don't have sufficient permissions to allow applications to create/write event log. Is this true? If so, that's insanely stupid.
Is there a work-around that doesn't involve running the application as administrator?
"Why don't you tie a kerosene-soaked rag around your ankles so the ants won't climb up and eat your candy ass..." - Dale Earnhardt, 1997 ----- "...the staggering layers of obscenity in your statement make it a work of art on so many levels." - Jason Jystad, 10/26/2001
|
|
|
|
|
You should be able to write to an event log, its creating an EventSource that you cant do using a normal account.
This was the case pre-vista as well. generally you create the event source using an installer that must be run as adminsitartor to succeed.
|
|
|
|
|
Exactly what J4amieC said. Just to add, that typically I create necessary event sources during the setup process since the setup is often (in my cases) ran using an administrator account.
The need to optimize rises from a bad design.
My articles[ ^]
|
|
|
|
|
Dear all I'm looking for some advice.
An access 2003 app exist on a corporate network but does not have the functionality required. IT won't support a connection to their SQL server and the app needs to be redevloped to included additional functionailty.
There are a number of locations where staff logon to a shared drive and need to update information in the database. There's around 10 users.
My question is should I redevelop the app to be a desktop application (c#) with an access backend or use something else.
Thank you for any information you can offer.
|
|
|
|
|
Have a look at the compact database, offered by microsoft. Its free and is just a file that would be placed on a share that is backed up. You could then write a c# winform app to sit ontop of it.
It really depends where you skillset is, I would do the above, as i could do that quicker than using access (as i have not used access for a lonnnnng time)
Mark
|
|
|
|
|
Why not use SQL Server Express Edition. If you build a totally new instance (on a separate machine), could the suppport be arranged since it's not disturbing any of the existing instances. Express edition is free and it's targeted for multi-user environments like Access, but has more capabilites (Compact edition cannot be used in multi user environments and all other editions aren't free to use).
Mika
The need to optimize rises from a bad design.
My articles[ ^]
|
|
|
|
|
Use the Express edition of SQL Server. It should provide you plenty of functionality without having to deal with your IT not sharing their server.
"The clue train passed his station without stopping." - John Simmons / outlaw programmer
"Real programmers just throw a bunch of 1s and 0s at the computer to see what sticks" - Pete O'Hanlon
"Not only do you continue to babble nonsense, you can't even correctly remember the nonsense you babbled just minutes ago." - Rob Graham
|
|
|
|
|
|
Hello everyone,
For the exception constructor,
Exception Constructor (SerializationInfo, StreamingContext)
http://msdn.microsoft.com/en-us/library/tz6bzkbf.aspx
I have two questions,
1. I saw some code defines it as public and some other code defines it as protected. What are the different purposes of different definitions?
2. I saw some code which defines a new exception type derives from System.Exception, and implements this contructor, but the implementation code is just call the base class constructor, and at the same time, the class is marked with Serializable tag. Like this.
I think such type of implementation is useless since the implementation of constructor is empty (just call base class contructor and the class is already marked with Serializable tag), so it is system default behavior and it should be ok to just mark it with Serializable tag to achieve the same effect.
Any comments?
[Serializable]
public class MyExceptionClass : Exception
{
public MyExceptionClass (string errorMessage)
{
}
public MyExceptionClass (SerializationInfo info, StreamingContext context) : base (nfo, context)
{
}
}
thanks in advance,
George
|
|
|
|
|
George_George wrote: Any comments?
Yes, as usual you need to read the documentation (In this case of SerializableAttribute, ISerializable and Exception).
|
|
|
|
|
Thanks J4amieC,
I asked two questions. Your reply "yes" is for which one?
regards,
George
|
|
|
|
|
You need to implement this constructor because constructors are not inherited.
|
|
|
|
|
Thanks Le Centriste,
This constructor you mean "Exception Constructor (SerializationInfo, StreamingContext)"? Why you say "because constructors are not inherited"? When I inherit from a class, all public methods should be inherited and constructor is also inherited and could be called by base keywords. Any comments to clarify?
regards,
George
|
|
|
|
|
All public and protected methods are inherited, except the constructors.
Suppose the following:
public class A
{
public A()
{
}
}
public class B : A
{
public B(int i)
{
}
}
A a = new A();
B b1 = new B(5);
B b2 = new B();
If B does not define an empty constructor, it does not inherit it. There is one subtle thing happening here the compile does not tell you. Since B's only constructor does not specify which base class constructor to call, it calls A's empty costructor silently.
Consider the following code:
public class A
{
public A(string s)
{
}
}
public class B : A
{
public B(int i)
{
}
}
B b = new B(5);
Since B does not specify which constructor from A to call, the compiler tries to place a call to A's empty constructor, but it does not exists, hence the error.
The following code would work:
public class A
{
public A(string s)
{
}
}
public class B : A
{
public B(int i) : base(i.ToString())
{
}
}
B b = new B(5);
So, in your case, the base class defines a constructor for serialization, but you class does not inherit it.
|
|
|
|
|
Thanks Le Centriste!
1.
You are so cool! I almost understand your points. Let me clarify. I think you mean even if the constructor in derived class MyException (below) did nothing but just do the same as base class, and if I do not include this constructor in derived class, it will hide the same signature constructor in base class, so that for an instance of derived class, we can not call this contructor (base constructor will not be called and found automatically, and base class constructor will be hide)?
public MyExceptionClass (SerializationInfo info, StreamingContext context)
2.
How about my question #1 in my original question? What is the difference between marking this contructor to be protected and to be public? Any special usage scenarios?
regards,
George
|
|
|
|
|
1. You are on the right path.
2. A good case would be with abstract classes, where all constructors are made protected, because there is no point having public constructors in an abstract class.
|
|
|
|
|
Thanks Le Centriste,
My class MyException is a class of the final level (e.g. be used by other components directly). I think I may be wrong. If I mark it as protected, during serialization, the constructor will not be called since from outside protected contructor could not be called?
regards,
George
|
|
|
|
|
You can make the constructor protected only if you need to prevent access to this constructor from child classes. Else make it as public.
|
|
|
|
|
Thanks Navaneeth,
If I mark the constructor as protected, I think it will be invoked when the instance is de-serialized, and since it is also protected, it means only the sub-class of this class is able to de-serialize the instance?
regards,
George
|
|
|
|
|
The same question is answered many times in MSDN as well as here. Still you are not clear?
2 - Because the constructors are not inherited. So it allowes to pass the parameters when you are instantiating child class.
|
|
|
|
|
Thanks Navaneeth!
Why you say "the constructors are not inherited"? When I inherit from a class, all public methods should be inherited and constructor is also inherited and could be called by base keywords. Any comments to clarify?
regards,
George
|
|
|
|
|
George_George wrote: Why you say "the constructors are not inherited"? When I inherit from a class, all public methods should be inherited and constructor is also inherited and could be called by base keywords. Any comments to clarify?
Here[^]
|
|
|
|
|