i have a simple code just have a look End Class
[Code]...
When i add num1 and num2 as above, compiler gave error that -- Operator + is not defined for types "type" and "type".How to define the meaning of '+' or any other operator in such situations?
I have defined a Sub in vb.net, with 'Of' type parameter like this:
[Code]...
I want to just add number1 and number2, But as you can see error has occured where i want to sum number1 and number2 saying that '+' is not defined for type 'VarType'. how to add these variables in Such Methods.
I am having a structure that is actually a simple byte with more functionality.[code]...
If there would be a way to inherit from Structure I would simply inherit from Byte adding my functionality, basically I just need a byte Structure with custom functionality.
My question is also valid when you want to define your new singleton member value-types (like, you want to define a nibble-type for instance etc.) and you want to be able to set it with an assignment to number or other language typed representation.
In C# you can use the implicit keyword to define an implicit user-defined type conversion operator.
In VB.NET you can define a CType conversion operator that will explicitly convert a user-defined type into another type.
Is there a way to declare an implicit conversion operator in VB.NET?
i wonder if it's possible to define a variable/property of more than one type. Let's say i want a property TextWebControl that is a WebControl and also implements Web.UI.ITextControl(f.e. like a TextBox or Label). But i don't want to enforce that it is a TextBox or Label, but only one that inherits from WebControl and also implements ITextControl so that it also would work with controls added in future releases of .Net-Framework.
.Net-Framework 4.0
Edit: I have retagged the question and added VB.Net because it's my default language. Normally it's no problem for me to understand C# also, but i must admit that it's difficult to translate generic stuff to VB.Net without experiences and it's also better documentated in C# than in VB. So i would appreciate(and aceept) a working example of a VB.net generic type of ITextControl/WebControl.From Marc's answer i understand that i need a generic class. But how do i instantiate it in SomeClass? This won't compile:
Class SomeClass
Public Property info As InfoControl(Of WebControl, ITextControl)
End Class
Public Class InfoControl(Of T As {WebControl, ITextControl})
End Class
Is there any way to define a Generic in VB.NET which will accept only Singles or Doubles? I tried the following things, based on what I've found online, but none compile:
Dim target As Nullable(Of {Single, Double})
Dim target As Nullable(Of T As {Single, Double})
Dim target As Nullable(Of T {Single, Double})
Dim target As Nullable(Of Single, Double)
Dim target As Nullable(Of T As Single, Double)
I want to specify that target can either be a Single? or a Double? only.
in Delphi I have:
type osVer = (
osVerUnknown,
osVerWin95,
[code]....
I need to translate to VB...
I am trying to query for records where that column IS NULL:
Dim UnassignedSubSvc =
From c In CurrentContext.SubService
Where c.Product.ProductSubServiceId **is null**
Select c).ToList()
I have the following NHibernate Linq query:
From eachLine In myNhSession(Of SamplePoco)()
Where eachLine.SampleIntField = 1234
The property SamplePoco.SampleIntField is type Nullable(Of Int32)
When I run the query, I get the following exception:
System.InvalidCastException: Unable to cast object of type 'NHibernate.Hql.Ast.HqlCoalesce' to type 'NHibernate.Hql.Ast.HqlBooleanExpression'
If I change the property type to Int32, it works. It seems that Nullable types are automatically converted into a coalesce expression by the Linq compiler.
Debugging the NHibernate, I just found out that this Where clause was converted into: {where ((eachLine.SampleIntField == 1234) ?? False)}. As I can understand, the whole condition comparison was translated to be coalesced instead of just the Nullable property.
If I put this way eachLine.SampleIntField.Equals(1234) it doesn't work as well ('Equals not implemented' exception)
If I change the query to the following code, it works:
From eachLine In myNhSession(Of SamplePoco)()
Where {1234}.Contains(eachLine.SampleIntField)
Another code that works as well (coalescing the field properly as I was expecting by the first query):
From eachLine In myNhSession(Of SamplePoco)()
Where If(eachLine.SampleIntField,0) = 1234
NOTE: I am mixing VB and C# - snippets come from different librariesI have a VB class definition as follows:
Public Class Session(Of TConnectionBuilder As {DbConnectionStringBuilder, New}, _
TConnection As {DbConnection, New}, _
TDataReader As {DbDataReader})
[code].....
I define 3 arrays: ID(n), Hour(n), Showed(n). If Hour(i) = actual time, I get the data pointed by ID(i), if not Showed(i).
BUT... I can add new hours or modify some existent, but I need to have the Hour array sorted. If I sort this array, the ID and Showed will point to different data.
So I though some different solutions:
1 - To make a string array with all inside (a 7 characters ID, a 5 characters Hour and 1 char for showed (T or F)). It could work, but, how can I sort the middle part of the array (Hour)? So, this don't work.
2 - A 3 dimensions "multitype" matrix (1 dimension of type Integer, the second of type Date and the third of type Boolean). I have no idea about how this can be done.
3 - A 3 dimensions string matrix, some like the "all inside" array: ID converted to a fixed size string, hour converted to a 5 chars string (hh:mm) and Showed converted to T or F. And sort the second dimension.
4 - Sell my copy of Visual Studio and drive a taxi cab
I get the error
Handles clause requires a WithEvents variable defined in the containing type or one of its base types.
in the following code..
Public Sub selCurrentManuf_SelectedIndexChanged(ByVal sender As System.Object, ByVal e As System.EventArgs) _
Handles selCurrentManuf.SelectedIndexChanged
End Sub
The drop list to go with it is the following...
<asp:DropDownList
OnSelectedIndexChanged="selCurrentManuf_SelectedIndexChanged"
selectedvalue='<%#Container.DataItem("c1_manufidcurrent")%>'
[code]....
I created a lable to handle DateTime = Now, It works fine. but when I moved it inside a FormView I Get the following Message. Handles clause requires a WithEvents variable defined in the containing type or one of its base types?
View 5 RepliesPublic Class Form1
Private Sub Button1_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles Click, Open.Click,Name.Click
SelectVid.ShowDialog()
End Sub
[code]....
I keep getting this error:
Error1'.' expected.
Error2Handles clause requires a WithEvents variable defined in the containing type or one of its base types.
Error 2 is also error 3
I am auto generating data grid and I am using check box in Data grid View,Now i am invoking check box state changed event but it produces the following error Handles clause requires a With Events variable defined in the containing type or one of its base types.
Here the code
Private Sub PRNT_CheckedChanged(ByVal sender As Object, ByVal e As System.EventArgs) Handles PRNT.CheckedChanged
Some Stuff.
End Sub
I am in the processing of moving an app from VB to C# but some of the classes I will just be moving to VB dlls to access from the main C# app. In doing this I am trying to get the VB dlls to utilize the main C# class lib. In this C# lib I have an abstract clase called base process, it sets up a background worker and handles all the progress tracking, errors, and even reports an ETA. To use this in a derived class in C# you would just do this...
public class SomeLongProcess : Common.Multithreading.BaseProcess
{
public void start()
[code]....
The problem is that if I do the equivelant in VB I get an error "Handles clause requires a WithEvents variable defined in the containing type of one of its base types". Well I can't do a WithEvents in the base class because it is C# so..
I am trying to follow this thread
[URL]
and I have it pretty close but have one error.
Quote:Handles clause requires a WithEvents variable defined in the containing type or one of its base types.
That error is on both of these, in blue
Private Sub SpellChecker1_DeletedWord(ByVal sender As Object, ByVal e As NetSpell.SpellChecker.SpellingEventArgs) Handles SpellChecker1.DeletedWord
'save existing selecting
[code]....
I have added the reference, I have also added them to the toolbox. My dictionary is all set. What did I miss?
Where X is a variable with a character stored in it. Works: If X = " " Then Valid = False Doesn't work If X = not " " Then Valid = False So what is the correct syntax? For the second one I get operator '=' is not defined for types Char and Long.
View 3 RepliesI get an Operator not defined error at "SetAttr(j = fo.GetFolder("C:\Documents and Settings\a19238\My Documents\VB Grille OrderTest\"))"
[code]...
I am working on a site that I would like to pass information from one page to another. For some reason I keep getting the above error.
//Code
Partial Class Customer
Inherits System.Web.UI.Page
[Code].....
I am working on a site that I would like to pass information from one page to another. I'm new to asp.net but not other languages, I'm just trying to learn some stuff. For some reason I keep getting the above error. The code I am using looks real similar to the code in the Murach book I am looking at
View 6 Repliesi am getting errors on last two event handlers. what did i do wrong?
Error - Handles clause requires a WithEvents variable defined in the containing type or one of its base types.D:Shipping ApplicationShipping ApplicationForm1.vb75136Shipping Application
Error - 'PrintDocument1' is not declared. It may be inaccessible due to its protection level.D:Shipping ApplicationShipping ApplicationForm1.vb1119Shipping Application
[code]....
I have a problem with Operator '&' someone may with this problem.
[Code]...
I am trying to concate string and system.type using operator & in VB and i am getting error :
[Code]...
I am trying to convert a piece of C# code, and I ran it through a converter, and had to make some changes.I am now running into this error:
Operator '<<' is not defined for types 'Char' and 'Integer'
The code is:
a += CType(URL(k + 0) + (URL(k + 1) << 8) + (URL(k + 2) << 16) + (URL(k + 3) << 24), UInt32)
b += CType(URL(k + 4) + (URL(k + 5) << 8) + (URL(k + 6) << 16) + (URL(k + 7) << 24), UInt32)
c += CType(URL(k + 8) + (URL(k + 9) << 8) + (URL(k + 10) << 16) + (URL(k + 11) << 24), UInt32)
The error occurs on each of the (URL(...) << X)
Just upgraded a VS 2005 ASP.NET 2.0 website to VS 2008 ASP.NET 3.5. There was an error on the Sub Button_Click. It seemed to be a minor error, the website and the button worked just fine, as usual. What does the error mean?
Protected Sub btnDEreports_Click(ByVal
sender As
[code]...
Error 20 Handles clause requires a WithEvents variable defined in the containing type or one of its base types.
i try to put picture in mysql with vb.net, first i convert with this function : [code] i try to use that function for storing picture to mysql database : INSERT INTO myImage (image) VALUES ('" & convertImage(PictureBox1.image) & "');and then i have this error : Operator '&' is not defined for types 'String' and '1-dimensional array of Byte'i create a table (myImage) with image field (LongBlob)
View 1 Repliesi am downloading data from xml using linq library those data i want to add them on a textblock item
TextBlock1.Text = TextBlock1.Text & result
but it has an error :
Error 1 Operator '&' is not defined for types 'String' and 'System.Xml.Linq.XElement'.
When i am changing this line to :
TextBlock1.Text = TextBlock1.Text & result.Tostring
it works but it adds this data :
"<"data> data <"/data>
instead of :
hello
I am having a problem in the following codes
Problem in "'" & rawData & "'")"
Error Message Operator '&' is not defined for types 'String' and '1-dimensional array of Byte'.
Complete Coding:
Private Sub Button1_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles Button1.Click
Dim fileSize As Integer
Dim rawData() As Byte
[code]....
I have set my datasource on my datagridview to be a subset of rows as follows:
dg.DataSource = myDataSet.testTable.Select("id=" & id)
But I get a runtime error that Operator '=' is not defined for types 'Object' and '1-dimensional array of DataRow' There should be an easy way to do this that doesn't involve creating new tables, etc.