I was just wondering if it is possible to apply an attribute to a property within a business object (MyBusinessObject) such that after the DataSource of a grid is set to a List(Of MyBusinessObject), the visible property of the column will automatically be false. For example:
myGrid.DataSource = New List(Of MyBusinessObject)
Public Class MyBusinessObject
[code]....
here any algorithms/pseudocode for reading/parsing 3-column csv data and determining unique objects/attributes/values?
example data:
john,height,1.75
george,age,21
[Code]....
i have already implemented a solution of my own but it's too slow and i can't find any relevant literature on the internet.
VB GridView control will not allow code in the vb code file to access a data column that has its visible property set to false. When it is set to true, the data column can be accessed with no problem. Any suggestions as to how to correct this? I have looked through the documentation, text books, and I have not found anything that gave me any clue as to what the problem could be. I thought that the property was just applied to the column, not that it would remove the column from being accessible.
[Code]...
In a vb .net winforms app I am trying out something for "wide and shallow" children of a record. I use strongly typed business objects ( Strataframe ).My plan is to have a number of "child tables" collected in a dataset I drop on the form. they have no correspondence in persisted data, so the dataset is untyped and I am creating the schema through the property sheet for the tables. Each table is the datasource for a datagridview in the interface.
In my proof of concept sample, My main businessobject (CustomerBO) interacts with a SQL Server 2008 table with fields - pk, name, - and a third column which is currently varchar(max) as I considered XML but could just as easily be varbinary(max) if that works better for holding the serialized dataset.
bo.bigfield will be the strongly typed prop I want to hold the byte() array or XML or whatever that represents the dataset for that record.So, the question in a nutshell - how do I convert a dataset to a single datum and reproduce the dataset from that datum. This is my first foray into datasets, datagridviews as well so if there are better ways to accomplish any of that I'm listening.
using an object-binding I have a an object representing "Employee". The employee has an ID-property. The ID of the employee must be unique.
My validation of the entered data is handled in the property set part of the object. In general, I validate criteria belonging to the object to validate only (eg numeric range of the ID, if it's value is not empy, ...). But in this case I need to know all ID's from the other employees. My tried this:
''' <summary>
''' Set EmployeeID
''' </summary>
[Code].....
Having an issue with my data gridview. I've set the visible property of the ID column to false, and in the designer the column is hidden, yet it still shows up when i run it. Now if i set it to True it shows the column twice.
View 3 RepliesI am trying to add an attribute to a dropdownlist control to store a value returned for the database. This value is need to get a code once a selection is made on the dropdownlist;
I have tried the following:
ddlStatus.DataTextField = dsValues.Tables(0).Columns("Description").ToString ()
ddlStatus.DataValueField = dsValues.Tables(0).Columns("CategoryCode").ToStrin g()
ddlStatus.Attributes.Add("SysCode", dsValues.Tables(0).Columns("SystemCode").ToString( ))
ddlStatus.DataBind()
but the attribute is not bound to the control
I have created a wpf vb.net project and am trying to set a simple databing. I'm not quiet sure how to set my DataContext = this; in the codebind. Currently when i run the program my Label never is updated. I have included my code below. [code]....
View 1 RepliesI tried applying an animation to an object in powerpoint through VB.NET. I'm only a beginner and have tried my best to figure it out with something like the following code which is two objects using one as the trigger. I managed to get it working in pptVBA but just can't get it to work in .NET. I keep getting an error COMException was unhandled.
Imports PowerPoint = Microsoft.Office.Interop.PowerPoint
Dim intereffect as powerpoint.effect
Dim oShape/sPic as powerpoint.shape
With oApp.ActivePresentation.Slides(1).TimeLine.InteractiveSequences.Add(1)
[Code] .....
I have a LinkLabel on a form that has its Text property bound to a strongly-typed DataSet. When the user closes the page, I call BindingContext.Item(_ds.UserSettings).EndCurrentEdit() and then serialize the data if _ds.HasChanges = True. However, HasChanges is always False.
Has anyone else done this with a LinkLabel?
I just like the LinkLabel in this scenario. I guess I could hide a TextBox off of the side of the form and bind to it, instead.
Due to a discussion in another thread , I am starting to use business object in an 3-Tiered windows app. As a starting point, I am trying to build objects/classes on a table from my database.
The database table has the following columns:
ID
TypeID
Reference
[Code]....
The issue I'm currently having is mapping multiple GUI fields to object properties (i.e. Presentation layer to Business Logic Layer mapping). To be more specific, this is in VB.Net 2.0 WinForms. The nature of the solution requires us to have 4 columns which exhibit the same type of behavior on our GUI - each column consisting of 11 textboxes (we'll just use this small sample size, as the problem extends beyond 11 textboxes).
What I am currently doing is setting the tag of each textbox in all four columns to a value like so:
Textbox1.tag = "name"
Textbox2.tag = "type"
Textbox3.tag = "speed"
[Code]...
As you can see this can get very bad, rather quickly. Currently we're setting 43 some odd properties that can be mapped to -- thus that select statement is extremely long -- many of which are embedded in multiple methods to try and attempt DRY (I've watered down the code to essentially a conceptual implementation).
Question is: how can I refactor this? I've attempted using a dictionaries/hashes to a certain extent, but it either became overly complex, or just plain didn't make an implementation sense as it convoluted the problem even more.
I have a custom business object called Customer and a Form1 with a BindingSource1, NumericUpDown1, TextBox1 and ComboBox1 and the attached code. Setting break points in the Property Sets shows that the Set for the ComboBox never fires at all even though the Set for the NumericUpDown and TextBox fire like crazy. [code]
View 1 RepliesI have completed a simple database for a project. Only 6tables. Of the 6, one is a "lookup" table.There is one "master" table that is the driver for the system. It is referenced as a foreign key by the other four tables.Give that this step is completed. What is the FASTEST, EASIEST way to create POCOs/BizObjects that can load load the data and the child data.Here are my CAVEATS.
I don't want to spend more than 30-60 minutes learning how? There is very little biz logic needed in the POCOs. They will pretty much load data. Don't even really need to write back data.I already know CSLA (up to version 3) but I feel that is overkill for this little project.Nevertheless, I would love it if it ROOT objects could have collection classes that contain the CHILD objects as in CSLA...but again, without using CSLA.
I have been trying for 2 weeks now to get this program to work.I am using VBasic and MS Access 2007 in conjuntion with a software application.the Database has 2 fields
1) Text
2) OLE Object (.jpg)
when I try to preview the data inside the DataSet I can only get the text to come threw, but that isn't the problem...the problem is binding the data to a datasource and displaying the information.I cannot get the database to display the information in FIELD 2
Okay, so I have a Generic IList of custom objects that I want to use as a datasource for a repeater.
Dim productRows As IList(Of MyCustomObject)()
'fill list with data
rptResults.DataSource = productRows
[code]......
I have an object, called 'PERSON' This person object has a title, firstName & Surname property as well as many other which are at the moment irrelevant. It also has a read only property called Fullname which concatenates the two or three parameters mentioned above depending on an optional parameter 'withTitles' passed over when you call PERSON.FULLNAME
PERSON.FULLNAME(true) <- Will add titles if there are any
PERSON.FULLNAME(false) <- Will give the name without the title
Public ReadOnly Property FullName(Optional ByVal withTitle As Boolean = False) As String
[Code]...
I get an error: PERSON does not contain a property of 'FullName'. If I change this to any other property that does not take a parameter it works as expected. Now I'm guessing that the binding procedure can't handle optional or mandatory parameters for object properties, is this right? Is there a better way to do it? I thought about looping through the collection to add them manually but that kinda defeats the object of DataBinding!
I need to generate a table from a List(Of Students). My Student class has properties for AcademicYear, TeachingSet, Surname and Forenames, is sorted in that order and also properties for ID and start date. The table should nest TeachingSets within AcademicYears and then the students within the TeachingSets, as shown in the table I've mocked up at http:[url]...
Using a repeater I get
08-10 students B74394 Mzejb Bsppn
08-10 students B74395 Lbuifsjof Bvti
08-10 students C68924 Epoob Cmpblf[code].....
I'm developing a business model for an application where I am representing physical entities. The hierarchy created from this is neat, but as I'm doing this, I'm beginning to think about things like, what properties should be included in one that may already be apart of another? Or what if some properties are expected to be in one object, but another object needs to return that value, how does it communicate that request through the hierarchical chain? And what is the best practice for this design?
[Code]...
But then I got to thinking, what if I have a ConnectionPoint entity and I want it to return which Panel it has? Should it have it's own Panel association as well? Or should there be a method/pattern for communicating the request up the chain? And again... what's typical best practice?
I have a function that returns a list of account numbers as an Arraylist. I am trying to use each account as a command parameter in another sub routine to get more data about each account number. This only returns the data for the last account number in the arraylist. I need to use each account number, call the database, get the additional information and store ALL of the data into a Gridview (databind). Example: If I had 3 account numbers in my arraylist return 3 rows of data to the gridview. I am struggling with how to get ALL of the information for each value (account number) in the Arraylist. Can someone point me in the right direction?? I think this can be done but I am not certain if my approach is correct or not. Perhaps I need to create datatables that contain the additional information for each value passed via the arraylist.
Private Function ReturnMultAccts(ByVal strAcct) As ArrayList
Dim acctsDetail As New ArrayList
Dim dsn As String = Configurati
[code].....
Please can you translate the above line of C# into VB.NET?At runtime, I'm trying to update an existing GridView column, as opposed to adding new columns, just before a DataBind()
View 7 RepliesI'd like to have an updateable DataGridView that's bound to a database-driven business object. It needs to handle all aspects of CRUD and be sortable and filterable as well.
Most of them simply bind to an object (non-database, manually filled) and do not allow you to Add, Delete, and Edit records. Furthermore, they basically never show how you would perform sorting and filtering.
I think the biggest things I'm not understanding are:
1) How do you make the DataGridView perform additions, deletions, and edits on an object.
2) How do you program your object to handle additions, deletions, and edits. Do you just need methods that use ADO.Net, NHibernate, or Linq to SQL (or any other CRUD handling mechanism)?
3) How to make this filterable and sortable.
Is this overly difficult to do or why am I have so much trouble finding examples for this?
How can I shift the GET-implementation of a Class property to a / using a custom attribute? (I've added instantation vars (classname, propertyname) to the attribute, however I'd rather have these automatically fetched ofcourse.)
Public Class CustomClass
<CustomAttributeClass(ClassName:="CustomClass", PropertyName = "SomeProperty")> _
Public Property SomeProperty() as String
Get() as String
[code]....
i wrote a custom attribute and got the following Color property that I want the user to be able to indicate the color property in the attribute on a class:
Private _ColumnColor As System.Drawing.Color
Public Property ColumnColor() As System.Drawing.Color
Get
[Code]....
[Code]...
Why is the first line not correct? What it wants is a System.Type and a System.String but refuses to work.
I have a class created for use with the PropertyGrid control in a VB.Net application. One of the properties of the class is:
Private _someProp As String
<Browsable(True), _
BindableAttribute(False), _
[code].....
I think know how to do this in C# but I'm having syntax trouble in VB.NET because I need to take advantage of the 'handles' event stuff. I have different events that I somehow (probably delegate) need stored in a property of an attribute (I just add an attribute to a property linking to the corresponding event).
E.g.
<BindEvent(EventThing)>_
Public ReadOnly Property IsTrue() As Boolean
Get
Return True
End Get
End Property
They need to be events so that other programmers can use the VB.NET handles keyword on methods.
Public Delegate Sub TestEvent(ByVal sender As Object, ByVal e As Object)
Public Event E As TestEvent
Public Sub Test() Handles E
End Sub
These properties are already raising a general event, which I am catching, determining the related property and thus getting the related attribute (and delegate/event). I want to then raise the event that's related. If I just use a delegate tied to the particular event that won't raise other handlers will it? I also want to avoid having to write a sub for each property that just uses Raise Event on the event type if possible as this seems redundant.
E.g. avoid:
Public Event E As TestEvent
Public Sub CallE(ByVal sender As Object, ByVal e As Object)
RaiseEvent E(sender, e)
End Sub
[Code] .....
Consider this scenario:
Class MyClass
Property SubProp1
End Property
[code]....
Next, I put an instance of MyButton into a property grid, expand property MC and edit SubProp2.From the type editor for SubProp2, I want to get hold of the attribute applied to property MC.Looking at the context,PropertyDescriptor.ComponentType, we arrive at Type: MyClass.If i look at the attributes applied to MyClass, though, it will only return the attributes applied directly to MyClass, and not the extra attribute applied to the property MC.
I have done some searching, but am still having trouble trying to set the browsable attribute of property to false at runtime in order to hide in the properties grid control (based on certain conditions).
View 9 RepliesWhen i set visible property of a control.
What happen with that control ? It merely hide or disposed from memory away ?
