Property Default Values in C#

[shapper]

Hello,

I have a class with a few properties:

public class PageViewData {
public string ContentType { get; set; }
public string Keywords { get; set; }
public string Title { get; set; }
}

What is the correct way to define a property default value in case the
property is not defined?

Thank You,
Miguel

[Jon Skeet [C# MVP]]

Re: Property Default Values in C#

On Sep 29, 3:12 pm, shapper <mdmo...@gmail. comwrote:

Hello,
>
I have a class with a few properties:
>
  public class PageViewData {
    public string ContentType { get; set; }
    public string Keywords { get; set; }
    public string Title { get; set; }
  }
>
What is the correct way to define a property default value in case the
property is not defined?

You can't do it directly using automatically implemented properties -
other than by setting the properties in the constructor(s) of course.
There are a few things like this where automatic properties could be
made more pleasant fairly easily. It would be nice to see them tweaked
for C# 4, but I don't expect that to happen. Maybe for C# 5 -
particularly as part of a push towards making immutability easier.

Jon

[Alberto Poblacion]

Re: Property Default Values in C#

"shapper" <mdmoura@gmail. comwrote in message
news:9c6bfab0-28bf-4691-838e-cf0b420791b7@b1 g2000hsg.google groups.com...

I have a class with a few properties:
>
public class PageViewData {
public string ContentType { get; set; }
public string Keywords { get; set; }
public string Title { get; set; }
}
>
What is the correct way to define a property default value in case the
property is not defined?

Use the "old" syntax, and assign the default value to the private
variable that stores the property:

private string contentType="de faultValue";
public string ContentType
{
get { return contentType; }
set { contentType = value; }
}

[=?iso-8859-1?B?S2VyZW0gR/xtcvxrY/w=?=]

Re: Property Default Values in C#

Hi Miguel,

there are two ways: Either initalize all values
to some default stuff in the Class Constructor,
or use attributes on the classes like e.g. this:

[CategoryAttribu te("Progress Bar"),
Browsable(true) ,
ReadOnly(false) ,
BindableAttribu te(false),
DefaultValueAtt ribute(typeof(C olor),"DarkGree n"),
DesignOnly(fals e),
DescriptionAttr ibute("The Progress Bar Color that will be used to
draw the Progress Bar")]
public Color ProgresBarColor {

get {

return this.colorProgr essBar;
}

set {

this.colorProgr essBar = value;
this.progressBa rBrush = new
SolidBrush(this .colorProgressB ar);
}

}

its a piece of code that i use in my extended
progress bar class. See the .NET Documentation
for more information about attributes and the
information about the classes in this example,...

Regards

Kerem

--
-----------------------
Beste Grüsse / Best regards / Votre bien devoue
Kerem Gümrükcü
Latest Project: http://www.codeplex.com/restarts
Latest Open-Source Projects: http://entwicklung.junetz.de
-----------------------
"This reply is provided as is, without warranty express or implied."
"shapper" <mdmoura@gmail. comschrieb im Newsbeitrag
news:9c6bfab0-28bf-4691-838e-cf0b420791b7@b1 g2000hsg.google groups.com...

Hello,
>
I have a class with a few properties:
>
public class PageViewData {
public string ContentType { get; set; }
public string Keywords { get; set; }
public string Title { get; set; }
}
>
What is the correct way to define a property default value in case the
property is not defined?
>
Thank You,
Miguel

[Marc Gravell]

Re: Property Default Values in C#

Either initalize all values

to some default stuff in the Class Constructor,
or use attributes on the classes

Attributes won't change the value, though - they are used mainly to
determine whether a value should be saved, and to reset the value
(akin to ShouldSerialize {name} and Reset{name}). Generally you need
code in the ctor, or a field initializer (which you can't do with auto-
implemented properties).

Marc

[shapper]

Re: Property Default Values in C#

On Sep 29, 3:24 pm, "Alberto Poblacion" <earthling-
quitaestoparaco ntes...@poblaci on.orgwrote:

"shapper" <mdmo...@gmail. comwrote in message
>
news:9c6bfab0-28bf-4691-838e-cf0b420791b7@b1 g2000hsg.google groups.com...
>

I have a class with a few properties:

>

 public class PageViewData {
   public string ContentType { get; set; }
   public string Keywords { get; set; }
   public string Title { get; set; }
 }

>

What is the correct way to define a property default value in case the
property is not defined?

>
   Use the "old" syntax, and assign the default value to the private
variable that stores the property:
>
private string contentType="de faultValue";
public string ContentType
{
   get { return contentType; }
   set { contentType = value; }
>
}

I see, so it is exactly the same as in VB.NET. I though, since C# has
automatic properties, that this would be different.

Thanks,
Miguel