473,811 Members | 3,213 Online
Bytes | Software Development & Data Engineering Community
+ Post

Home Posts Topics Members FAQ

ExpandableObjec tConverter and CollectionBase

Hi,

I'm using classes with the ExpandableObjec tConverter attibute in a
UserControl for properties. This works fine for some classes, and properties
of these classes can be edited during design time.
However, classes which are derived from CollectionBase don't save their
values in the form's code. Properties can be changed in the VStudio property
editor but they are not persistent:

// Property values are saved in the forms code.
// e.g. "this.userContr ol11.Test.Value = 5;"
[TypeConverter(t ypeof(Expandabl eObjectConverte r))]
public class TestClass {
private int _i = 0;
public TestClass() {}

[DefaultValue(ty peof(int), "0")]
public int Value {
set {_i = value;}
get {return _i;}
}
}

// Problem: Property values can be changed but are NOT saved in the forms
code
[TypeConverter(t ypeof(Expandabl eObjectConverte r))]
public class TestClassCol : CollectionBase {
private int _i = 0;
public TestClassCol() {}

[DefaultValue(ty peof(int), "0")]
public int Value {
set {_i = value;}
get {return _i;}
}
}

Does anybody know how to make collection base derived classes save their
values in the form code ?

Many thanks in advance,

Marcus
Dec 8 '05 #1
0 1532

This thread has been closed and replies have been disabled. Please start a new discussion.

Similar topics

5
3543
by: Steve M | last post by:
I have subclassed CollectionBase. I have also implemented GetEnumerator(). I have tried to set the DataSource of a DataGrid to an instance of my subclass. However, the items in the grid are not obtained via the Enumerator that I create in the GetEnumerator() method. I have tried elplicitly implementing IEnumerable on my sublass as well. Can anyone help on this? Thanks in advance.
1
3471
by: Pol Bawin | last post by:
Hi, I have a objectA with a property that return an object B (accessor GET only) I have defined an ExpandableObjectConverter on the type B and overrided CanConvertTo, CanConvertFrom, ... The problem is that can not edit the object B (the proerty in greyed) in the propertyGrid (I can edit these properties but not the object directly because, it doesn't have SET accessor) In fact, when I edit this object, I woul like to change just the...
5
5921
by: Eric Johannsen | last post by:
I have a simple object that inherits from CollectionBase and overrides the Count property: namespace MyTest { public class CollTest : System.Collections.CollectionBase { public override int Count { get { return 0; }
0
3045
by: Vladimir.Sakharuk | last post by:
I have created ExpandableObjectConverter in C#. for use in System.Windows.Forms.PropertyGrid. The property grid shows the DiffItem is a object that holds member TheItem. without expanding TheItem It works if u click, select from drop down box. until you DoubleClick it shows error: "Invalid property Value". with "Object type cannot be converted to target type."
0
2207
by: Adriano Coser | last post by:
Hello. I'm facing the exact problem described here: http://groups.google.com/groups?hl=pt&lr=&threadm=%23cs%24KWF%24BHA.2200%40tkmsftngp02&rnum=1&prev=/groups%3Fhl%3Dpt%26lr%3D%26q%3DTypeConverter%253A%253AGetProperties%26meta%3D I made a ExpandableObjectConverter subclass but its GetProperties method is not called when my object is set as a Converter of PropertyDescriptor. The thread above gives a good explanation of the problem, but...
0
1108
by: Adriano Coser | last post by:
Hello. I have an ExpandableObjectConverter subclass that I associate to the 'Converter' of a custom property descriptor. After I changed my .net code to the new syntax (VC 2005), the GetProperties method of my converter class is not called anymore by the PropertyGrid. Now my expandable properties always show a property 'Length' with value 0.
2
6967
by: Samuel R. Neff | last post by:
What's the advantage of inheriting from CollectionBase as opposed to just implementing IList? It seems that it saves you from having to implement a few properties (Clear, CopyTo, Count, GetEnumerator, and RemoveAt) but the way it implements all the other things you need to override seems overkill and counters the advantage of having an extensible base class. For example, the documentation example implementation of Remove: Public...
2
7105
by: =?Utf-8?B?TWFyayBDb2xsYXJk?= | last post by:
I've created a usercontrol with a Person property. The Person property returns a Person object. I've also created a PersonConverter class which inherits the ExpandableObjectConverter so the Person property is expandable in the PropertyGrid. This all works fine. I've also created another usercontrol that also has a Person property and returns a Person object. But in this usercontrol I don't want the Person object to be expandable. What...
0
1209
by: Rohan | last post by:
Hello, i am doing a custom class for my property for a property gird using ExpandableObjectConverter. I have a class (CustomFontClass) that uses a Converter which inherits the ExpandableObjectConverter. everything works fine, but the only thing that doesn't work is that the MyNewFontList NEVER calls the SET. I have followed the http://www.codeproject.com/KB/vb/using_propertygrid.aspx example in the example its the same case . any idea...
0
9607
by: Hystou | last post by:
Most computers default to English, but sometimes we require a different language, especially when relocating. Forgot to request a specific language before your computer shipped? No problem! You can effortlessly switch the default language on Windows 10 without reinstalling. I'll walk you through it. First, let's disable language synchronization. With a Microsoft account, language settings sync across devices. To prevent any complications,...
0
10652
Oralloy
by: Oralloy | last post by:
Hello folks, I am unable to find appropriate documentation on the type promotion of bit-fields when using the generalised comparison operator "<=>". The problem is that using the GNU compilers, it seems that the internal comparison operator "<=>" tries to promote arguments from unsigned to signed. This is as boiled down as I can make it. Here is my compilation command: g++-12 -std=c++20 -Wnarrowing bit_field.cpp Here is the code in...
1
10408
by: Hystou | last post by:
Overview: Windows 11 and 10 have less user interface control over operating system update behaviour than previous versions of Windows. In Windows 11 and 10, there is no way to turn off the Windows Update option using the Control Panel or Settings app; it automatically checks for updates and installs any it finds, whether you like it or not. For most users, this new feature is actually very convenient. If you want to control the update process,...
0
9211
agi2029
by: agi2029 | last post by:
Let's talk about the concept of autonomous AI software engineers and no-code agents. These AIs are designed to manage the entire lifecycle of a software development project—planning, coding, testing, and deployment—without human intervention. Imagine an AI that can take a project description, break it down, write the code, debug it, and then launch it, all on its own.... Now, this would greatly impact the work of software developers. The idea...
0
5561
by: TSSRALBI | last post by:
Hello I'm a network technician in training and I need your help. I am currently learning how to create and manage the different types of VPNs and I have a question about LAN-to-LAN VPNs. The last exercise I practiced was to create a LAN-to-LAN VPN between two Pfsense firewalls, by using IPSEC protocols. I succeeded, with both firewalls in the same network. But I'm wondering if it's possible to do the same thing, with 2 Pfsense firewalls...
0
5700
by: adsilva | last post by:
A Windows Forms form does not have the event Unload, like VB6. What one acts like?
1
4346
by: 6302768590 | last post by:
Hai team i want code for transfer the data from one system to another through IP address by using C# our system has to for every 5mins then we have to update the data what the data is updated we have to send another system
2
3874
muto222
by: muto222 | last post by:
How can i add a mobile payment intergratation into php mysql website.
3
3026
bsmnconsultancy
by: bsmnconsultancy | last post by:
In today's digital era, a well-designed website is crucial for businesses looking to succeed. Whether you're a small business owner or a large corporation in Toronto, having a strong online presence can significantly impact your brand's success. BSMN Consultancy, a leader in Website Development in Toronto offers valuable insights into creating effective websites that not only look great but also perform exceptionally well. In this comprehensive...

By using Bytes.com and it's services, you agree to our Privacy Policy and Terms of Use.

To disable or enable advertisements and analytics tracking please visit the manage ads & tracking page.