C# - Using Iteration Variable In A Lambda Expression?
Feb 16, 2012[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"?
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.net - "Using The Iteration Variable In A Lambda Expression May Have Unexpected Results"
Jun 27, 2012Edit: Here is a much more simpler example of this issue (i've deleted my original question):
Dim numbers1 As New List(Of Int32)({1, 2, 3})
Dim numbers2 As New List(Of Int32)({3, 4, 5})
For Each n1 In numbers1
' no warning '
Dim contains = numbers2.Contains(n1)
Next
[Code]...
The local variable number1 is redundant and makes the code less readable as @Meta-Knight already has emphasized. Note: All three ways are safe and give the correct result.
Get: "iteration Variable In A Lambda Expression May Have Unexpected Results"
Mar 1, 2012Possible Duplicate:Why is it bad to use a iteration variable in a lambda expression.why do I get: "iteration variable in a lambda expression may have unexpected results"? Suppose I have the following code:
[Code]...
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For i = 0 To 10
Dim num = (From n In numbers Where n Mod i = 0 Select n).First()
Next
[code].....
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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
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Feb 22, 2009From 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]...
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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)(....)
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[Code]...
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Public Class Cheque
Public Property Id As String
Public Property Status As Byte
[code]....
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[code]...
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private void Join()
{
_receiveBuffer = new byte[MAX_MESSAGE_SIZE];
[code].....
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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]'.
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xxx, _
If(dr.Table.Columns.Contains("EnterpriseID"), dr.Field(Of Integer)("EnterpriseID"), -1), _
xxx
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Function(dr, x, t, dflt) _
If(dr.Table.Columns.Contains(x), dr.field(Of t)(x), dflt)
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xxx, _
xCol(dr, "EnterpriseID", GetType(System.Integer), -1), _
xxx
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Private Sub InsertItemInCache(Of T)(ByVal item As CachedItem(Of T), ByVal dependency As AggregateCacheDependency, _
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[code].....
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Dim reportdataforpage = (From reportvar In reportdata Where reportvar.reportpage = pagenum)
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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]....
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Instead of using the lambda expression I can also write the function and call it as argument like this:
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If u.DvRoleID = 2 Then
Return True
[Code] .....
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Delegate Function Criteria(ByVal u As User) As Boolean
Public Function GetReviewer1(ByVal u As User) As Boolean
If u.DvRoleID = 2 Then
[Code] .....
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Public Function CreateController(requestContext As System.Web.Routing.RequestContext,
controllerName As String)
[Code].....
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[Code]...
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I need to write a generic function like[code]....
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