I have inherited a vb6 app that I am trying to upgrade to VB2008.
If I can find out that a control has a ToolTipText property as below, how can I get the value?
For
Each ctl In frm.Controls
If Not (ctl.GetType().GetProperty("ToolTipText") Is Nothing) Then
[Code].....
I thought I saw how to do this but can't seem to find it now.Is there a way to set the properties of all controls on a Form by Control Type?Meaning, if I have 5 textboxes on a form can I write code like .If page.contol is TextBox then
textbox.forecolor = Blue
Then when the page loads is sets all the textboxes forecolor on the form to Blue.
I am creating a User Control where I have a property called Items. Items is of type LibraryPanelBarItem Collection (custom class) which contains a collection of LibraryPanelBarItem objects. I would like to be able to add these at design time by using the Collection editor that VS uses for adding things such as treenodes/listviewitems. Ideally I would also be able to declaratively add them to the html syntax. I can get the Items property to show up but I get no intellisense to add the items between the opening and closing tags. [Code]
View 1 RepliesIs it possible to create a user control with a list of custom class type property? If it is, how can I? The issue is that, in designer mode the property is not displayed in property window. I can add the list on markup but when i switch to the designer mode it gives an error which is 'The user control does not have a public property named BookList'.
View 1 RepliesI have a requirement where I need to have a "type safe" way of accessing property names, without actually instantiating an object to get to the property. To give an example, consider a method that takes as arguments a list of IMyObject and a string that represents a property name (a property that exists in IMyObject).
The methods implementation will take the list and access all the objects in the list using the property name passed... for some reason or another, we won't dwell on that!!
Now, I know that you can do this using an instantiated object, something like ...
Dim x as MyObject = nothing
Dim prop As PropertyInfo = PropHelper.GetProperty(Of MyObject)(Function() x.MyProperty)
Where my helper method uses reflection to get the name of the property as a string - there are numerous examples of this flying around on the web!
But I don't want to have to create this pointless object, I just want to do something like MyObject.MyProperty! Reflection allows you to iterate through a types properties and methods without declaring an object of that type... but I want to access a specific property and retrieve the string version of its name without iteration and without declaring an object of that type!
The main point here is that although I am trying to get the property name as a string... this is done at run time... at compile time, I want this to be type safe so if someone changes the property name, the compilation will break.
I would like to be able to set Control visual properties such as color, boarder, flat style, etc. on the base class of the control so that as I add new instances of the control, each instance inherits the visual properties of the base. I have tried using Application Settings but it appears as though I need to reference an application setting manually each time I add the control to a form. This is a Windows Form question.
View 4 RepliesI'm trying to make a program with transparent labels over pictureboxes and when I set the label Parent to the PictureBox the position of the label changes.
View 2 Repliesi frequently have troubles with the dock property. it seems that either the order of creation or adding to the parent control determines whether or not a control's dock property supersedes another's. e.g. a control with the dockstyle fill will overlap with another docked control on the same parent. does anyone know what the rules are to determine how docking will behave; particularly in dynamically created GUIs?
View 2 RepliesIs there a way to bind the text property of a control to an expression? I have a user control that I add to a FlowLayoutPanel. You can see I have 4 controls in the FlowLayoutPanel below. The first control is a LinkLabel and the other three are my user controls which are numbered 1, 2, & 3. I'd like to bind the label that shows the 1, 2, or 3 to the user controls index within the FlowLayoutPanel.
If I happen to remove the 2nd user control I want the 3rd user control to now display 2. I could use the FlowLayoutPanel ControlAdded or ControlRemoved events, but wanted to see if I could do some binding first.
If I need access to the value of a user control's property BEFORE PreRender, would I need to base the custom control off of one of the preexisting data controls (repeater, listview,etc.)?One of my user controls features a gridview control that is configured based on the user control's properties on which it resides. Several of the key properties alter the SQL Statement for the underlying recordsource. I'm now in a situation where the property that sets the WHERE statement for the SQL Statement needs to tied to a value in the user control's parent FormView. Think of the formview as displaying a customer detail record. The user control takes the customer's account number and then displays data from a related table such as Customer Contact Names. Since the gridview is created before the control's prerender event, working within the prerender event doesn't seem efficient.
View 1 RepliesI have a function which creates a different type of expression depending on the value of the variable passed in.[code]...
View 1 RepliesI have a "generic" Tag class which holds an ItemValue, which at this time is declared as Object. The ItemValue could be one of several datatypes; String, Boolean, Integer, etc. Is there a way to create a class property to identify which data type the Tag is?
I've tried this but it's not working;
Public Property DataType As Type
Get
Return m_DataType
[code]....
I would like to check if a property's type is an interface (not a specific interface, but any interface).
dim __PropertyInfo As PropertyInfo
dim b as boolean = isinterface(__PropertyInfo)
[code].....
I'm currently trying to create a class that is a composition of the SqlDataAdapter class (as unfortunately you can't inherit from it). In order to try and make it as similar as possible I'm using all the same inherits and interfaces as is documented on MSDN.The problem that I am having is that there are some properties where the interface specifies that the type of the property is IDbCommand. But in the SqlDataAdapter the property type is SqlCommand.
View 3 Replieshow to set up the filter property to look for more than one file type? msdn says we can set the filter to '*.*' or *.txt' etc, but doesn't say how to specify more than one type.I've tried a pipe delimited string but it didn't seem to work e,g '*.txt |*.log|*.xml'.
View 2 RepliesIn my ASP.NET app, I'm using classic ADO 2.8 to save some data into an Access database. (Or a Jet database, for those who insist that Access is just the front-end.) So I have a RecordSet containing some data, and I want to set the value for some fields, but first I need to know the field type. So I use the Recordset.Type property:
Dim fieldType = rs("MyField").Type
And that unexpectedly results in an error: MissingMethodException was unhandled by user code -- Error: Missing method 'instance valuetype ADODB.DataTypeEnum [MyProjectName] ADODB.Field::get_Type()' from class 'ADODB.InternalField'.
Considering that it is .NET itself that has created the .NET/COM interop assembly, any idea why?And here's the strangest thing: When the debugger stops and reports the error and takes me to the spot in my code where it happened, and it has that great feature by which you can hover the mouse over any variable etc. and it will show its value -- so I hover over the rs("MyField").Type part, and, lo and behold, it shows the correct value!So if it could evaluate it at debug-time, why did it throw an error at run-time?
I have in my My.Settings four settings [code] now I want to get the value of the current setting from the My.Settings.SettingName. [code]
View 1 RepliesIs there a way for a property to access its own name and type at runtime using reflection? I want to access this info without hard coding the name or index of the property in the class.
Simple Example Code:
Private ReadOnly Property MyProperyName() As String
Get
Console.WriteLine((Get Current Property Info).Type.ToString)
Console.WriteLine((Get Current Property Info).Name)
[code]....
I have an App where I'd like to be able to edit any type (font, colour, point etc.) at run time and use any of the .Net default type editors. (e.g., font/ colour picker).
Rather than re-invent the wheel, I decided to use the property grid control.
If I pass an object of, say font, to the grid, it lists all the fields separately, with no option to open the font picker.[code]...
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]......
I'm trying to create a generic function to build a Linq expression from a list of Telerik grid filters. I'm trying to stay clear of dynamic Linq. Because I don't know the type that I'm building the expression for, I'm attempting to use reflection in the lambda functions to refer to a property, but after applying the fix suggested by @JaredPar I get the error, "The LINQ expression node type 'Invoke' is not supported in LINQ to Entities." Is there any way around this? here is my code:
Public Shared Function buildRadFilter(Of T)(ByVal filterExpression As List(Of GridFilterExpression)) As Expressions.Expression(Of Func(Of T, Boolean))
Dim returnPred = PredicateBuilder.True(Of T)()
[Code]....
I have an app that allows the user to choose an image, at design time, either as a straight image, or from an image list.
All cool so far, except that this is not happening from the visual studio property browser, its happening from a property grid that is a part of a type editor.
My problem is, both the image picker (actually resource picker), and the imagelist type converter rely on some design-time services to get the job done. In the case of imagelist, its the IReferenceService and in the case of the resource picker its a service called _DTE.
In the first instance of an edit from the visual studio property browser, I could get a reference to these services but (1) how can I add them to the type descriptor context of my property grid?
It would be better, for future proofing, if I could just copy a reference to all of the services in the type descriptor context. (2) Where does the property browser get these services from in the first place?
ETA: I still don't know how to do it, but I now know it is possible.
(1) Sub-class control and add a property whose type is an array of buttons.
(2) Add it to a form.
(3) Select the new control on the design service and edit the new property in the property browser.
(4) The collection editor dialog pops-up
(5) Add a button
(6) Edit image and image list - the type editor and type converter, respectively, behave as they should.
ETA2: Ok, I'm getting warm. It looks like you do it through the Site property of the property grid. I can create a new site, and pass it the type descriptor context I have a reference to and then it should have all the service. I'll give it a go ...
I have a class and one of the properties is a list of a custom class. The caller gets the list and is adding instances of class to the list. How do I get notified that the list has been updated?
Private _list as List(of MyType)
Private _totalField1 as Integer
Public Property MyTypeList As List(Of MyType)
Get
Return _list
End Get
Set(ByVal value As List(Of MyType))
_list= value
_totalField1 = _list.Sum(Function(x) x.Field1)
End Set
End Property
What I'm trying to do is every time a MyType object is added to the list keep a running total of Field1, but adding to the list doesn't use the setter. How can I know when the list has been added or changed?
I've got a custom NumericEditor control that has a nullable Decimal property called Value. When I bind a data field to Value, I'd like to retrieve the underlying Type of the data that's bound, so that I can restrict the use of decimal places if the source field is an integral data type.I figure I'd have to do this in the BindingContextChanged event, but how do I get the Type of the data field from the binding itself? My Google-Fu is failing me at the moment.
In short, I'm looking for something like the GetValueType method mentioned in the following question: Simple databinding - How to handle bound field/property change. Winforms, .Net I imagine this method would also be handy if the Value property was an Object.
I need to be able to tell if a property is of type List(of T)but am currently unable to. if i do
TypeOf (UpdateTo.GetType.GetProperty(node.Name)) Is System.Collections.Generic.List(Of Object)
I get the following error
TypeOf (UpdateTo.GetType.GetProperty(node.Name)) Is
System.Collections.Generic.List(Of Object) Expression of type
'System.Reflection.PropertyInfo' can never be of type[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.
I am building a code behind page that has a public property (MyDTOItem) which is essentially a DTO object (dtDTOItem) Note: In my code the Get and Set are actually real code (I stripped it for the example).The problem I am having is in the Page_Load event. When I set the .Member1 property of the DTO object the Get code runs and not the Set and therefore the DTO ibject property .Member1 never gets assigned. I figured out that if I add code (MyDTOItem = New dtDTOItem) to the Page_Load event then it will set the value correctly. What I am trying to figure out is how to initialize the property object without having to do it explicitly. It has to be an extended property because I have custom Get and Set code.
Public Property MyDTOItem As dtDTOItem
Get
End Get
Set(value As dtDTOItem)
[code]....
I am building a code behind page that has a public property (MyDTOItem) which is essentially a DTO object (dtDTOItem) Note: In my code the Get and Set are actually real code (I stripped it for the example).
The problem I am having is in the Page_Load event. When I set the .Member1 property of the DTO object the Get code runs and not the Set and therefore the DTO ibject property .Member1 never gets assigned.
I figured out that if I add code (MyDTOItem = New dtDTOItem) to the Page_Load event then it will set the value correctly. What I am trying to figure out is how to initialize the property object without having to do it explicitly. It has to be an extended property because I have custom Get and Set code.
Public Property MyDTOItem As dtDTOItem
Get
End Get
[code]....
I am writing a math game for my brother in Visual Basic to help him with double digit numbers(both adding and subtracting).Normally you solve a problem by writing right to left on a piece of paper. Is there any way of setting the text box to do this?
For Example:
58
+ 18
You would type in the text box '6' followed by '7' so it would read '76'I set the right to left property but it does not do what I want it to do.
My LINQ query is as follows
Dim Query = From t In New XPQuery(Of xUser)(Xpo.Session.DefaultSession)
.Where("Name=John").Select("new (Name as FirstName)")
Unfortunately i get the error No property or field 'John' exists in type 'xUser'.Of course no such property exists in my xUser class, but hot can i fix that?After reading within the DynamicLinq Class i found this function
Function FindPropertyOrField(ByVal type As Type, ByVal memberName As String, ByVal staticAccess As Boolean) As MemberInfo
Dim flags As BindingFlags = BindingFlags.Public Or BindingFlags.DeclaredOnly Or _
If(staticAccess, BindingFlags.Static, BindingFlags.Instance)[code]...
How can i edit my "faulty" query? What am i doing wrong here?
