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FileHelpers - Creating a field object

I am trying to dynamically add field properties to a record class that I am also building dynamically using FileHelpers.Dynamic.DelimitedClassBuilder. I have no issues creating the class object and I currently add a field using the AddField(String) method.
As my apps grows I now have a need to declare specific field properties in various situations. So in the same sense I wanted to use FileHelpers.Dynamic.DelimitedFieldBuilder to create a field object and then pass that to my DelimitedClassBuilder object using the method AddField(DelimitedFieldBuilder).
However I am unable to instantiate a new object using FileHelpers.Dynamic.DelimitedFieldBuilder. When I issue the following code I get an error stating that DelimitedFieldBuilder does not contain a constructor that takes two arguments.
FileHelpers.Dynamic.DelimitedFieldBuilder fb = new FileHelpers.Dynamic.DelimitedFieldBuilder("ClassName", "Type");
Looking at the documentation it appears that this class does only have properties associated with it, so I am kind of stuck on how to actually implement this. It seems like it should be fairly easy but I cant seem to figure it out. Thanks for any help.

Not familiar with that functionality of file helpers; however, in the vast majority of functions/methods across .NET there is usually a way to assign properties after the class is instantiated.
Try something like this:
FileHelpers.Dynamic.DelimitedFieldBuilder fb = new FileHelpers.Dynamic.DelimitedFieldBuilder();
fb.Whatever = "ClassName";
fb.otherwhatever = "Type";
Just a stab. I have no idea if it will work or not.

The constructors of DelimitedFieldBuilder are internal so you'll run into difficulty with your approach. However AddField(String) returns a DelimitedFieldBuilder, so you might be able to use that.
It might be easier to make your own class MyFieldBuilder which calls the standard AddField(String).

Get all writeable properties of an ADLDS-Class

I'm developing an application which can deal with a MS-ADLDS-Service.
Currently it is possible to create Directory-Entries and assign values to some properties.
Not a realy exciting task until this:
Im my application it's possible (it should be) to configure which properties of a class (for instance: the CN=Person class) should be assigned with values which are evaluated at runtime in my application.
Long story short:
I want to retrieve all (writeable) properties of a class. Without creating and saving a new CN=Person-Object before.
Currently i use my schemaBinding to get the Directory-classSchema-Entry of the Person-Class (CN=Person) from where i read some property-values (like "AllowedAttributesEffective", "mayContain", "AllowedAttributes") - i get the most properties by this way - but some Properties are missing! For instance the "telephoneNumber"-Property (attributeSchema: CN=Telephone-Number)
Does anybody know how to get these properties of a class? ADSI-Edit does this: when i create a new object with adsi-edit i can assign values to all possible properties before committing the new entry.
thanks a lot for any hint!
(.net code is welcome)

I have found the solution for my task!
Some of these properties are "calculated" and not persistent at the directoryentry.
So its meant to call the RefreshCache() Method and pass the needed property names as an string array.
directoryEntry.RefreshCache(new string[] { "allowedAttributesEffective",
"allowedAttributes",
"systemMayContain",
"systemMustContain" });
After that call, the properties have values....
if (directoryEntry.Properties["systemMayContain"]).Value != null)
{
/// Success
}

NHibernate entity design with a private member

In my database I want to save the user GUI settings for one of the "views", as a semicolon-separated string, i.e. : "1;31;5;411;".
I use NNibernate for this project, and this is the mapping and the code for this specific private member;
C# entity code for User.Settings
private string _linkConsole = "0";
[DataMember]
public LinkConsole LinkConsole
{
get { return new LinkConsole(_linkConsole); }
set { _linkConsole = value.GetSqlString(); }
}
XML mapping:
<property name="LinkConsole" type="System.String" access="field.camelcase-underscore" not-null="true"/>
LinkConsole has a lot of public methods for GUI-specific settings, which is toggling the values of certain private members.
When its time to save this settings to the database, .GetSqlString(); formats the string and writes it to the private member _linkConsole , which is the private member exposed to NHibernate & the database.
Problem:
When I try to do something with the GUI, i.e.:
User.Settings.LinkConsole.SetRightPaneContent(50);
This is never stored on the object LinkConsole, and I can't seem to figure out why?
When I set a breakpoint, I get a message in Visual Studio stating:
Your step-into request resulted in an automatic step-over of a property or operator
Maybe this is a result of the problem, that I'm designing this in a wrong way?
If so, is it possible to achieve this in combination with a private string member?
Any help would be greatly appreciated! Thanks! :-)

Have you considered implementing a custom IUserType for LinkConsole for use as the NHibernate type?
The use case you're describing is exactly what IUserType is for.

This isn't really an NHibernate issue. LinkConsole is a reference type. If you set a member of it, it isn't going to call the set method on the property you got it from, it's going to set the value on the instance that was returned from the original get. If you want this code to work, you'd need to get a new LinkConsole instance from the User, call the methods to set the settings, then set the LinkConsole property of the user to your configured instance.

The problem is probably with how you are setting the private variable that is being written to the database. Without seeing your code I can't be sure but look at the following article to be able to step into properties with visual studio:
http://msdn.microsoft.com/en-us/library/cc667388.aspx

Discriminator Property

Working through this step by step guide.
I am trying to create the inheritance between BirthAppointment / tblAppointment. However I need the Discriminator Property to be set to appCatId.
The appCatId is held within tblAppointmentType. How can I access this.
alt text http://www.zero7web.com/RegBook-linq.jpg
Thanks in advance for your help.
Clare

Am I understanding correctly that you want BirthAppointment to inherit from tblAppointment? If this is the case, discrimnator property is a field in the database table that used to distinguish records that represent tblAppointment objects from BirthAppointment objects. As such, you can't use appCatId since it lives in another table (tblAppointmentType).

You need to use Visual Studio's Properties window.
http://msdn.microsoft.com/en-us/library/bb531247.aspx

C# property attributes

I have seen the following code:
[DefaultValue(100)]
[Description("Some descriptive field here")]
public int MyProperty{...}
The functionality from the above snippit seems clear enough, I have no idea as to how I can use it to do useful things. Im not even sure as to what name to give it!
Does anyone know where I can find more information/a tutorial on these property attributes?
I would be also interested in any novel / useful tasks this feature can do.

The functionality from the above
snippit seems clear enough,
Maybe not, as many people think that [DefaultValue()] sets the value of the property. Actually, all it does to tell some visual designer (e.g. Visual Studio), what the code is going to set the default value to. That way it knows to bold the value in the Property Window if it's set to something else.

People have already covered the UI aspect - attributes have other uses, though... for example, they are used extensively in most serialization frameworks.
Some attributes are given special treatment by the compiler - for example, [PrincipalPermission(...)] adds declarative security to a method, allowing you to (automatically) check that the user has suitable access.
To add your own special handling, you can use PostSharp; there are many great examples of using PostSharp to do AOP things, like logging - or just code simplification, such as with automatic INotifyPropertyChanged implementation.

They are called Attributes, there is a lot of information in msdn, e.g. http://msdn.microsoft.com/en-us/library/z0w1kczw.aspx
In general they don't "do" anything on their own, they are used by some other code that will use your class. XmlSerialization is a good example: XmlSerializer (provided by Microsoft as part of the framework) can almost any class (there are a number of requirements on the class though) - it uses reflection to see what data is contained in the class. You can use attributes (defined together with XmlSerializer) to change the way XmlSerializer will serialize your class (e.g. tell it to save the data as attribute instead of an element).

The ones in your example is used by the visual designer (i.e. MS Expression Blend and Visual Studio designer) to give hints in the designer UI.
Note that they are metadata and will not affect the property logic. Setting DefaultValue for instance will not set the property to that value by default, you have to do that manually.
If you for some reason want to access these attributes, you would have to use reflection.
See MSDN for more information about designer attributes.

We use it to define which graphical designer should be loaded to configure
an instance of a specific type.
That is to say, we have a kind of workflow designer which loads all possible command
types from an assembly. These command types have properties that need to be configured,
so every command type has the need for a different designer (usercontrol).
For example, consider the following command type (called a composite in our solution)
[CompositeMetaData("Delay","Sets the delay between commands",1)]
[CompositeDesigner(typeof(DelayCompositeDesigner))]
public class DelayComposite : CompositeBase
{
// code here
}
This is information is used in two places
1) When the designer creates a list of commands, it uses the CompositeMetaData
to display more information about the command.
2) When the user adds a command to the designer and the designer creates
an instance of that class, it looks at the CompositeDesigner property,
creates a new instance of the specified type (usercontrol) and adds it
to the visual designer.
Consider the following code, we use to load the commands into our "toolbar":
foreach (Type t in assembly.GetExportedTypes())
{
Console.WriteLine(t.Name);
if (t.Name.EndsWith("Composite"))
{
var attributes = t.GetCustomAttributes(false);
ToolboxListItem item = new ToolboxListItem();
CompositeMetaDataAttribute meta = (CompositeMetaDataAttribute)attributes
.Where(a => a.GetType() == typeof(Vialis.LightLink.Attributes.CompositeMetaDataAttribute)).First();
item.Name = meta.DisplayName;
item.Description = meta.Description;
item.Length = meta.Length;
item.CompositType = t;
this.lstCommands.Items.Add(item);
}
}
As you can see, for every type in the assembly of which the name ends with "Composite",
we get the custom attributes and use that information to populate our ToolboxListItem instance.
As for loading the designer, the attribute is retreived like this:
var designerAttribute = (CompositeDesignerAttribute)item.CompositType.GetCustomAttributes(false)
.Where(a => a.GetType() == typeof(CompositeDesignerAttribute)).FirstOrDefault();
This is just one example of how you might be able to use custom attributes,
I hope this gives you a place to start.

These attributes customize the design time experience.
http://msdn.microsoft.com/en-us/library/a19191fh.aspx