Store Files

[david_day]

I'm currently using visual studios 2010 and targeting the .Net framework 4.0. Right now I'm building a customer management software in a windows form application. The class for my customer is very simple, it only stores properties and has one function to convert the date of birth to the person's age. The part that I'm struggling on is storing files that can be associated with the user. Currently the property that stores and comments on the customer is set up like this:

[FONT=Consolas][SIZE=2][FONT=Consolas][SIZE=2]    
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That is how I plan on setting up the documents property, storing the path location of the documents in a list(of string). However, I was wondering if there is any way to make a copy and store the physical document as opposed to simply storing the path location. How would I declare my list in that case, a list(of object)?

 

[jmcilhinney]

First of all, your property should be ReadOnly and have no setter. Think about it. Let's say that you add 10 comments to that List and then someone else assigns a new List to the property. You just lost your 10 existing comments. Pretty much every property in the .NET Framework that is a collection type (DataTable.Rows, DataTable.Columns, DataSet.Tables, Control.Controls, ListView.Items, ComboBox.Items, etc, etc) is ReadOnly. That allows you to get a reference to the collection in order to call its own Add and Remove methods but prevents you from replacing the collection itself with a new collection.

As for the question, what exactly do you mean by "the physical document"? You can't actually store files in your application. If the file contains text then you could store its contents in a String and a picture file could be loaded into an Image, but what about a PDF, Word document, Excel workbook, etc? You could load the file contents into a Byte array but what good would that do you? What exactly are you trying to achieve?

 

[david_day]

Great point on setting the property as ReadOnly. I'm definitely going to change that.

What I'm ultimately trying to do is essentially create a copy of the file and keep that copy. My fear is that if I store the path location and the user decides deletes the original, then that file is lost forever. PDF files are pretty much the only thing that will be saved, that and the occasional Word document, but that's about it.