Lazycoder

1. 

   Mike Schinkel
   March 27th, 2004 - 23:53

   Isn’t this what you needed? http://www.abstractvb.com/code.asp?A=1036

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2. 

   Mike Schinkel
   March 27th, 2004 - 23:58

   Oops. I posted the wrong one. The one you found was this one:
   http://www.abstractvb.com/code.asp?A=960 which had a typo; that wasn’t VB.NET’s fault;
   it was the fault of abstractvb.com.
   Here’s how you do it in C#: http://www.abstractvb.com/code.asp?A=999
   To do in VB, just use VB’s attribute syntax instead. The capabilities of
   VB.NET and C# are practically identical, the syntaxes are just different.
   It really is just a matter of personal preference.

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3. 

   Scott
   March 28th, 2004 - 01:38

   Mike,

   I think for the most part that’s true. The syntax is the same, but the usage is a little different.

   Here’s the code I was working on in both VB and C#

   [Bindable(true),Category("Items"),DefaultValue(null)]
   public System.Collections.ArrayList TabItems
   {
   get { return this._tabItems; }
   set { this._tabItems = value; }
   }

   <Bindable(False), Category(“Data”), DefaultValue(Nothing)> Property TabItems() As ArrayList
   Get
   Return _tabItems
   End Get
   Set(ByVal Value As ArrayList)
   _tabItems = Value
   End Set
   End Property

   The difference is, the C# version compiles and works. The VB one doesn’t. I want use the DefaultValue attribute to set a (duh) default value of null (nothing) on the TabItems property in the designer. What do I pass into the arguments for the DefaultValue attribute in VB? I tried “typeof(ArrayList)” I tried various combinations of GetType(typeof()) and so forth. The MSDN docs couldn’t tell me anything, every example either use boolean properties or string properties. I wanted to see an example of a property with a reference type, besides string, that used the DefaultValue attribute. I still haven’t figured it out, it was easy in C# so I just re-wrote the control in C#. It took about 10 minutes for me to re-write it.

   I started out dabbling in VB4 32bit, moved on to VB 5, and started using VB 6.0 while it was in beta. They’ve really screwed up VB, it can’t really be considered a RAD development tool anymore. Hopefully the Whidbey release will go a long ways towards fixing that situation.

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4. 

   Mike Schinkel
   March 28th, 2004 - 01:58

   Hmm. Well the default value for a object *is* “Nothing,” and there is no constant for any other valid object state, so maybe they don’t thing they need to implement on non-value types? If you *don’t* include the DefaultValue() as you were trying, does it not work for what you need? Or are you just trying to get it to work for a datatype that is not string or number for learning purposes?

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5. 

   Jim
   October 19th, 2004 - 07:34

   Try this:

   Default Public Property PropName(ByVal Value As Integer) as Integer
   Get
   Return _MemberVariable
   End Get
   Set
   _MemberVariable = Value
   End Set
   End Property

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6. 

   Pete Brown
   April 28th, 2005 - 08:33

   In my case, I did it with an image

   DefaultValue(GetType(Image), Nothing)

   Compiles and works fine.

   Pete

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7. 

   Mini-Tools Timm
   July 11th, 2006 - 21:06

   The way to do this is as follows:

   For other reference types, simply replace the GetType() value. For example, to set a default value for a string property:

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