using class libraries

Richard Brennan

I have created a class library project and made a class and it has built and made the dll.

I have added the reference to this dll to a different project and added the using directive.

I can use 'new' and instanciate a class from the dll. I have even used an array of this class. All is fine when I use the data on one form.

Here is the problem. I am loading data from a file into the class in the dll - and i need it to be available from all forms in may app - how do i make it possible to see my instanciation of the class across different forms. It is currently declared (using new) on the main form of the project.

I have tried instanciating the class in a static class but that is wrong.

6 Replies

Know the answer? Post it — somebody with the same question will find it here.

Vulpes15y ago
Accepted answer
It's best to expose global data via a static class:

internal static class Globals
{
internal static string[] Data;
}

To initialize the data:

Globals.Data = ......; // obtain data from class in dll

and to access it from any form;

string[] data = Globals.Data;
0
Richard Brennan15y ago
thanx dude got threre - i have instanciated the array - filled it in from one form and read it from a different form. U the man. cheers.
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Vulpes15y ago
Sorry, Richard, I'd missed out the word 'static' between 'internal' and Person[] in my previous post.

I've corrected it now.
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Richard Brennan15y ago
sorry vulpes - i just can make it work

This line in static class

internal Person[] people;

causes this error

Error 1 'global.people': cannot declare instance members in a static class.

Do u want to c my code?
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Vulpes15y ago
Well, a static class can only contain static members which is an advantage for global data because you don't need to create an instance to reference it - you just prefix the field or property with the class name. So, following the blueprint in my previous post:

internal static class Globals
{
internal static Person[] person;
}

To initialize the data:

Globals.person = ......; // obtain data from class in dll - can do this from anywhere

and to access it from any form;

Person[] _person = Globals.person;
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Richard Brennan15y ago
The following code generated this error.

Error 1 'global.person': cannot declare instance members in a static class C:\Users\Richard\documents\visual studio 2010\Projects\Web Spinner\Web Spinner\Global.cs 9 21 Web Spinner

public
{

static class global public Person[] person;
}

Person is the dll class and I need an array of them available for many forms to acces - how can I get that working in a static class
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