Imports System.Reflection
Public Class Test
[CODE]......................
'This line indicates a compile error: 'Expression does not procedure a value':
[CODE]..................
Imports System.Reflection
Public Class Test
Private Field As String
End Class
Module Module1
Sub Main()
Dim field = GetType(Test).GetField("Field", Reflection.BindingFlags.NonPublic Or Reflection.BindingFlags.Instance)
[Code]...
How would you convert this to VB (using .NET 4.0 / VS2010) ?
bw.DoWork += (o, args) =>
{
Code Here
};
I thought maybe like this:
AddHandler bw.DoWork,
Function(o, args)[code]....
But it says Function does not return a value on all code paths.
I have an inline lambda expression that I would like to use throughout my application. I just can't seem to find a reference on how to do this with more parameters than the element being tested. Here is a quick example of what I currently have.
Private Sub Test()
Dim List As New List(Of String) From {"Joe", "Ken", "Bob", "John"}
Dim Search As String = "*Jo*"
[Code].....
Why does this:Private [Function] As Func(Of Double, String) = Function(ByRef z As Double) z.ToString
gives the following error:Nested function does not have a signature that is compatible with delegate String)'.
While this:Private [Function] As Func(Of Double, String) = Function(ByVal z As Double) z.ToString
Does not? (The difference is ByRef/ByVal)
Furthermore, how might I implement such a thing?
I got this Error. below is my code.
GenerateTheList is function.Need help
Private Sub buttGenerate_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles buttGenerate.Click
Dim thread1 As New Thread(New ThreadStart(GenerateTheList))
thread1.Start()
End Sub
I just upgraded from Visual Studio 2005 to Visual Studio 2010 yesterday. I tried opening my site; it started the conversion wizard and seemed to work OK. However, I get the error "Visual Basic 9.0 does not support this kind of lambda expression." Here is my code:[code]....
The error is on the "Function()" line. I thought multi-line lambda functions were one of the new VS2010 features. Why am I getting a VB9.0 error in VS2010?
Ok so I have alot of plans for programs coming up and I want them all to fade in and out so instead of copy and pasting from project to project etc I learnt about dll's
So when I added in the references etc and I typed in what I declared the Fadein function as which was "FadeIn" I got an error saying it needed to be declared
So I declared it as a string
Private Sub Form1_Load(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles MyBase.Load
Dim FadeIn As String
FadeIn(Me)
End Sub
Then I get a different error saying Expression is not a method.
im migrating from vb6 to vb.net and have only very basic knowledge of .net. now i upgraded one of my projects, in which i had function cleartexts() which would clear all the text boxes of the forms. now to upgrade it to .net i converted it to sub (as it didnt return anything), so it looked like,
public sub cleartexts()
for i = 1 to 24
text(i).text=""
next
end sub
but .net 2005 gives the error, "expression is not a method", how do i call it then?? or what modifications do i need to make?
From this code
[Code]...
If I put New Action(AddressOf PrivateMesage), then I get the following error: Bounds can be specified only for the top-level array when initializing an array of arrays. on the following code
[Code]...
i have these 3 sets of code that are giving me INT() errors. Error: Expression is not an array or a method, and cannot have an argument list.
Code1:
Private Sub Form6_Load(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles MyBase.Load
Dim Browser As New WebBrowser
[code]....
. I get this error: "Cannot convert lambda expression to type 'string' because it is not a delegate type" - keyword select become underlined in blue
[Code]...
Above code should displays drop list of employees first name and last name in a combo box
I am new to nodes() method. I am getting the foloowing syntax when trying to create a stored procedure using the nodes() method.
The syntax error:
Msg 170, Level 15, State 1, Procedure spmTestSelect, Line 19
Line 19: Incorrect syntax near '.'.
[code]...
I am dumb founded at this statement....maybe its just too many hours/days of doing C# to VB.Net conversion but i am drawing a blank on this conversion.
List<string> sColors = new List<string>(this.CustomPaletteValues.Split(','));
try {
List<Color> colors = sColors.ConvertAll<Color>(s => (Color)(new ColorConverter().ConvertFromString(s)));
What i have so far:
Dim colors As List(Of Color) = sColors.ConvertAll(Of Color)(....)
As you can see its the content of the lambda that i am hitting a brick wall with.
In looking at Fuzzy Date Time Picker Control in C# .NET? Piotr Czaapla's answer to that question is exactly what I need. unfortunately, I'm a VB.NET guy and I'm not that familiar with lambda expresions, so my attempts to convert the code have resulted in hours of misplaced parenthesis and banging my head with a brick.
Any chance some bi-lingual wizard could convert the C# code to VB.net for me?
[Code]...
Using lambda's in VB.Net results in no intellisense. Is this a bug with VS2010 or expected? Note that it works fine in C#
Return Array.TrueForAll(chequeColl, Function(x) x.Number <> "N") 'No intellisense Number does not appear
Return Array.TrueForAll(chequeColl, Function(x As MyClass) x.Number <> "N") 'Now casted intellisense appears
UPDATE: Here's an example
Public Class Cheque
Public Property Id As String
Public Property Status As Byte
[code]....
How should the following C# code be converted to VB.Net? I have tried several code converters and none produce correct results.
[code]...
I will probably sound like a bad developer here, but I am attempting to convert some code from the following page from C# to VB.NET:The code I am having trouble converting is from Step 4 of "Joining a Multicast Group" on the page, and here is the code with the comment lines removed:
private void Join()
{
_receiveBuffer = new byte[MAX_MESSAGE_SIZE];
[code].....
I want to implement this function:
Public Function GetFunc(Of TSource, TResult) _
selector As Expression(Of Func(Of TSource, TResult)) _
As Func(Of TSource, TResult)
[code]....
UPDATE:I have the following issue, it's a part of a function:
Dim obj As Object = value
For Each exp In expressions
If obj Is Nothing Then Return [default]
[code]....
Exception Details:
ArgumentException:Object of type 'System.Linq.Expressions.Expression`1 [System.Func`3[System.Char,System.Char,System.Char]]'cannot be converted to type 'System.Func`3[System.Char,System.Char,System.Char]'.
If been try to convert some code I have from VB.net to C# but I just cannot get it working!first is the vb code I'm only interested in the line that has the Lambda Expression for the C#[code]......
View 2 RepliesCurrently, I have code similar to this:
xxx, _
If(dr.Table.Columns.Contains("EnterpriseID"), dr.Field(Of Integer)("EnterpriseID"), -1), _
xxx
I would like to create a Lamdba expression something like the following (this doesn't work):
Dim xCol As Func(Of DataRow, String, Type, Object, Object) = _
Function(dr, x, t, dflt) _
If(dr.Table.Columns.Contains(x), dr.field(Of t)(x), dflt)
So that I can say something like:
xxx, _
xCol(dr, "EnterpriseID", GetType(System.Integer), -1), _
xxx
I know in VB Lambda expressions must return a value and can only have one statement. But in my case I just need to execute a Sub that does not return a value. Is there a way to trick it by somehow returning a dummy value yet still call my Sub? If possible what would the syntax be like?
View 3 RepliesI am having an issue using the vb equivilant of the MAX lambda expression. at foos.Max(function(x) x.id) when I try to intellisense the property ID VS will not show it. But when i run the example it works. Is there something I am doing which is wrong, an i am just lucky it runs? [Code]
View 1 RepliesThere is the code:
Private Sub InsertItemInCache(Of T)(ByVal item As CachedItem(Of T), ByVal dependency As AggregateCacheDependency, _
ByVal key As String, ByVal updateCallBack As CacheItemUpdateCallback)
[code].....
[URL]..Module Module1
[Code]...
It says the result will always be 5 namely the final value of i. How come?
They don't put the iteration variable in the "closure"?
I am Creating a Lambda Expression, but it' not getting me the write Out put :
Public Class Form1
Delegate Function GetLastChar(ByVal S As String) As String
Private Sub Form1_Load(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles MyBase.Load
[code]....
I want Send a Name like "Arindam" and its return me "m", the last character.but in messagbox return value shows "fasle" I can't under stand why it's showing "False" instead of "m", the last character.
I am having a generic ListOf-collection holding the self-created User-object, I can filter for users by using lambda-expression like this:
Dim reviewers As List(Of User) = users.Where(Function(u) u.DvRoleID = 2).ToList
Instead of using the lambda expression I can also write the function and call it as argument like this:
Public Function GetReviewer1(ByVal u As User) As Boolean
If u.DvRoleID = 2 Then
Return True
[Code] .....
Now the question: why can't I create a delegate having the same signature as the GetReviewer1 function and use the delegate as argument inside the where-clause like this:
Delegate Function Criteria(ByVal u As User) As Boolean
Public Function GetReviewer1(ByVal u As User) As Boolean
If u.DvRoleID = 2 Then
[Code] .....
The compiler does not accept the crit delegate as argument.
I am trying to see if the controller class name is the name of the controller name passed in. I think my lambda expression is wrong and that is why it isn't working properly. I am passing in the correct controller names, but the export variable is always null.
Public Function CreateController(requestContext As System.Web.Routing.RequestContext,
controllerName As String)
[Code].....
In MSDN documentation defination about lambda expression is "A lambda expression is a function or subroutine without a name that can be used wherever a delegate is valid ". Here validity of delegate is necessery only when we are passing lambda expression as an argument to a method.
[Code]...
Lambda expression with ternary operator in VB?
View 15 Replies
