Change Default Value Of A Property Of Control?
Jan 12, 2012
I am inheriting my own DataGridView (say MyDataGridView) from the standard DataGridView control. What I want is that certain properties of MyDataGridView should have a different default value than what its base have. For example, AllowUserToAddRows, AllowUserToDeleteRows, AllowUserToResizeRows properties should have the default values of False; so that when I drag MyDataGridView into a form in the IDE, the default values shown in the properties grid should be False. Later on, if I want to change them to True from the grid, they will be set accordingly.
View 1 Replies
ADVERTISEMENT
Mar 10, 2010
I inherits textbox Control and I added some new properties to it .one of these properties value i want it to change it's value in desgin time when i change Name property of the new textbox
Public Class NewTextBox
Inherits TextBox
Private _txtSubName As String = String.Empty
That is the property for set or get SubstringName of Textbox
Public Property SubName() As String
Get
Return _txtSubName[code].....
that's the property i want to change it's value when i change Name property of the control.i tried to overrides Name property but it's not overridable also i trieds to overloads it but it doesn't work in desgin time.Here is something i tried but it's wronge.
Private _txtName As String = ""
Public Overloads Property Name() As String
Get[code]......
View 4 Replies
Jan 12, 2012
I am inheriting my own datagridview (say MyDataGridView) from the standard datagridview control. What I want is that certain properties of MyDataGridView should have a different default value than what its base have. For example, AllowUserToAddRows,
[Code]...
View 1 Replies
Aug 24, 2010
I am creating a customised version of the ListView control and there are several of the properties that a ListView has that I would like to be set to a different value to the ListView default when a user goes to use my user control.
From what I've found there seems to be a number of people suggesting just set them in the constructor, but to the best of my knowledge that would just mean that the user would not be able to change the properties in the PropertyGrid in the VS IDE.I assume this is probably something extremely simple that I have overlooked.
View 8 Replies
Jun 23, 2010
I have been trying to create a custom control based on the ListBox called FileListBox. I followed Microsoft's walkthrough but am having some trouble.
What I want is to add another property to the ListBox called SafeItems which is an ObjectCollection of strings (like the Items property). I will use the Items property to store a collection of Filenames as strings and I would like to store the corresponding SafeFilenames in the SafeItems collection.
This is what I've tried:
FileListBox.Designer.vb
<Global.Microsoft.VisualBasic.CompilerServices.DesignerGenerated()> _
Partial Class FileListBox
Inherits System.Windows.Forms.ListBox
[Code].....
View 6 Replies
Mar 27, 2011
I created a Custom Class and Implemented a Type Converter for it. I used this Custom Class as a new property of a Custom Control.Everything is fine at design time. I can set the values of this property but at run-time the values i entered resets back to the initial declaration i made.
View 5 Replies
Jan 22, 2012
If we say blue is the default colour of the Backcolor property I understand it as if you don't specify a colour for Backcolor blue will be its colour. But I could not make sense of default property of a class in the context of building a custom user control. After calling an instance of a class we have to either call one of its members or assign an other object for it. Therefore why should there be a default property?
View 9 Replies
Oct 6, 2010
how to invoke methods, but how does one change a simple property?
For demonstration-sake, here's a very simple set of code that should help. Let's say I need to set the visible property from a child form, and thus, it needs to be invoked:
Friend Sub activateItem(ByVal myItem As PictureBox)
If myItem.InvokeRequired = True Then
????
[Code]....
View 1 Replies
Apr 7, 2010
I can't seem to get this to work so I need a fresh set of eyes on it! I have a combobox dropdown with some names. When I select a certain name from the list, I want it to change the textbox property.I tried :if combobox1.selecteditem= "edward" thentextbox1.maxlength= "2"
View 2 Replies
Mar 26, 2008
In my never ending search for more knowledge, I have come across Partial Classes. I was wondering if some of the kind people who actually understand the uses could explain some of them to me. Now I know that when we create a form that we actually create a partial class which the generator rewrites when we add a control or change a property at design-time, and this allows us not to have to worry about setting up the controls ourselves.
[Code]...
View 2 Replies
Apr 1, 2010
I need some help to understand my options to get this working. I try to update a textbox control by a property-changed event from a class variable. I've digged around for a day and have a vague understanding that this can be solved in three ways:
1. Using some "if InvokeRequired", "Invoke" code in the handler method
2. By programming a special delegate class for this variable
3. By using a databinding directly linking the control (textbox) to the class event
Now.. Are these options correct? And would it be possible to get some help to show these three solutions in actual code (relevant to mine)? I can't seem to manage to sort all the information to a working code. Also, what are the pros and cons of the different solutions?
As my code stands now, it's obviously none of the above, as it gives a cross-thread error, as indicated.
[Code]...
View 2 Replies
Jan 5, 2009
I believe that the correct way to give a property a default value is to use the Default Attribute on the Property.[code]In the property window, the value that's displayed in a grid's property bag when it's newly dropped onto a form is False, not True. It does recognise that the default value should be True because it shows the value as bolded and then de-bolds it when we manualy set it to true - but it doesn't respect the default as the initial value. Is there any way of getting the property bag to respect the default value?
View 4 Replies
Aug 23, 2011
I have a control which has a button named "btn1", and I want to change it's contents through a dependency property in XML, like this:
<UserControl:UserControl1 ButtonContents="Something"/>
Here's what I have:
Public Class UserControl1
Public Shared ReadOnly ButtonContentsProperty As DependencyProperty =
DependencyProperty.Register("ButtonContents",
[code]....
But how can the dependency property know what to do?
View 3 Replies
Oct 7, 2010
For a given class, with a default property of list, you can access an instance object in the list by doing myClass.defProperty("key"). You can also achieve the same results by typing myClass.defProperty!Key.
I have been told that using the parenthesis and quotes is faster for the way the runtime accesses the Property, but I'd like to understand what is the difference and how do each work...
I understand C# has a similar behavior by replacing the parenthesis with square brackets.
View 1 Replies
Sep 27, 2011
Is there anyway to have a class that can return a default type without specifying the property.
If I had a class that had a few properties and one property returned a string value and others returned additional types, could I do the following?
Dim StudentGrade as new StudentGradeClass
'call and get default property
Dim CurrentGrade as string=StudentGrade
'instead of this
Dim CurrentGrade as string=StudentGrade.Current
The reason I am asking this is when I have classes that have other classes as properties and would like to just get a default return value,.
View 2 Replies
Mar 8, 2011
I'm attempting the following:Default Public Property Data(Of dataType)(ByVal key As String) As dataType
Get
Return DirectCast(values.Item(key), dataType)
End Get
Set(ByVal value As dataType)
values.Item(key) = value
End Set
End Property
[Code]...
It made more sense to make it a property, and it would be the default property of the class. The data type can not be specified on instantiation of the class, because it can contain multiple objects of different data types.
View 2 Replies
Oct 15, 2009
I'm attempting the following:
Default Public Property Data(Of dataType)(ByVal key As String) As dataType
Get
Return DirectCast(values.Item(key), dataType)
[code].....
View 2 Replies
Jan 5, 2012
I have a FontFamily property, but I don't know how set the default value:
Public UnitsFontFamilyProperty As DependencyProperty = DependencyProperty.Register("UnitsFontFamily", GetType(FontFamily), GetType(ValueAndUnit), New FrameworkPropertyMetadata(New
[Code]....
View 2 Replies
Jun 13, 2011
I'm converting Visual Basic.Net code to C# in my project. But I have some doubts on how to convert Visual Basic default property to C#. The first option that comes to me are the indexers. Lets imagine the next code in Visual Basic
Public Class MyClass
Dim MyHash as Hashtable
Public sub New()
[Code]....
View 2 Replies
Dec 22, 2011
The following XAML produces an AmbiguousMatchException. The DataContext for myText is a DataTable consisting of > 1 row which contains a DataColumn named "test":
<TextBox Name="myText" Text="{Binding Path=Rows[0].Item[test]}"/>
When I modify the binding path syntax to the below example, the binding works as expected:
<TextBox Name="myText" Text="{Binding Path=Rows[0][test]}"/>
Given that the name of the DataTable is "myData", both of the following lines of code reference the contents of the column "test" on row 0:
myData.Rows(0)("test")
myData.Rows(0).Item("test")
Why doesn't the syntax that explicitly names the Item property appear to work in a binding scenario?
View 1 Replies
Apr 2, 2010
I am new to classes, and I am new to Visual Basic in general, but I am working on a multi class program. The code seems to be correct, but I am trying on instantiate a class oject with the code:
View 3 Replies
Jul 4, 2012
I am making a new class that requires a lot of input information. Some of the properties need to be set to a default value, however I do not want to hard code them into the class.
What do you think would be the most efficient way to populate these properties?
I've been thinking of making a new class to hold all the default props and pass them as one object into the new class as a single argument but it seems kind of clunky.
View 2 Replies
Sep 16, 2009
Given a simple class like this:
Public Class clsOB
Implements System.ComponentModel.INotifyPropertyChanged
Private _Frequency As Double
Private _Value As Double
Public Event PropertyChanged(ByVal sender As Object, ByVal e As
[Code] .....
And then I'd like to do something like this:
Dim
o As
New
clsOB(50, 30)
o = 31
View 11 Replies
Jan 12, 2010
What is the difference between these two methods for defining property value defaults? [code] Is there a reason to use one method over the other for defining the default property values in a class?
View 24 Replies
Jan 13, 2010
I'm working on a simple base form in which all the other forms in the project will inherit. This base form only adds 5 properties (at the moment) dealing with painting a gradient background. The problem I'm facing right now is when I change a property on Form1 (the test form) and click run it doesn't show that change. I also checked the .designer.vb file and when I make a change it's not added to the code behind file, I'm at a loss right now to why.
[Code]...
View 5 Replies
Oct 28, 2010
I am getting a strange error when I try to build my solution. The error occurs when I am calling the oGetHeaderValue function and passing the parameters.
Dim oGetHeaderValue As New clsGetHeaderValue
Dim returnString As String
returnString = oGetHeaderValue(strInvoiceNumber, strOrderNumber)
The error message is: Class 'clsGetHeaderValue' cannot be indexed because it has no default property.
View 1 Replies
Nov 11, 2010
I use the following line of code within a single method to explicitly check and trust an SSL cert from the following host: MyTrustedCompany.com:
ServicePointManager.ServerCertificateValidationCallback = Function(obj As [Object], certificate As X509Certificate, chain As X509Chain, errors As SslPolicyErrors) (certificate.Subject.Contains("CN=MyTrustedCompany.com"))
No problem with the code -> works perfectly 100%.
The problem is, it is too far reaching. I thought its scope would only be within the method I decalred it, but apparently it is a Shared property on the 'ServicePointManager' object, and must then persist for the entire application, which I do not want.
The problem is later I am calling web services of mine, etc and getting the "Could not establish a trust relationship..." exception. This is because in the line of code above I check for the host name of an SSL cert specefic to that method. I quickly tested Returning 'True' from the callback so all certs would be trusted instead of checking for a specefic name (i.e. MyTrustedCompany) and subsiquent requests worked. This is how I know this callback assignment reaches father than that single method. Sure I could extend the callback to include all other certitificate names, but what I would rather do is set the 'ServerCertificateValidationCallback' back to its default behavior. Like the pseudo code below:
ServicePointManager.ServerCertificateValidationCallback = Nothing 'Default checking behavior
How do I remove the custom validation and set it back to its default behavior?
View 3 Replies
Mar 20, 2009
Option Strict Off
Option Explicit On
Module ModGlobal
[Code].....
End ModuleI am getting this warning s when i upgrade from VB 6 to VB.NET .,I am verz new to this Visual Basic .
View 1 Replies
Mar 11, 2009
I need to set the default property of a dotNet Control used by an VB6 Application.
<ComClass(myControl.ClassId, myControl.InterfaceId, myControl.EventsId)> _
<DefaultProperty("NewProperty")> _
Public Class myControl
[code]....
View 2 Replies
Apr 26, 2012
I am newer in VB NET.
VB code:
Public Class InputBox
Private Sub Button1_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles Button1.Click
Dim a, b, S, p
a = InputBox("Enter length")
b = InputBox("Enter width")
S = a * b
p = a + a + b + b
End Sub
End Class
In InputBox lines i get this error:
Class 'LearningVB.InputBox' cannot be indexed because it has no default property.
View 1 Replies
