I am trying to avoid every single function affecting my response time.therefore my question is using ToArray while converting generic list to array, does this take significant response time?should I use array directly while building my array within for each or working with list of and then at the endusing ToArray? any difference?
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I have a generic List(Of Customer). The customer class has a name, address, and phone number properties. I also have a property of another class that accepts a customer name array. I am able to do this by doing the following:
Dim names As String()
Dim i As Integer = 0
'customer.GetCustomers is a List(of Customer)
[Code]....
Is there a better way to convert this to a string array?
I have a function that works great in C# that I'm converting to VB.Net. I'm having an issue converting the result set to a generic list in VB.net.
The code:
Public Function GetCategories() As List(Of Category)
Dim xmlDoc As XDocument = XDocument.Load("http://my_xml_api_url.com")
Dim categories = (From category In xmlDoc.Descendants("Table") _
Select New Category()).ToList(Of Category)()
Return categories
End Function
The error occurs when convertng the result via .ToList(Of Category)() The error:
Public Function ToList() As System.Collections.Generic.List(Of TSource)' defined in 'System.Linq.Enumerable' is not generic (or has no free type parameters) and so cannot have type arguments.
Category is a simple object I've created, stored in the App_Code directory.
I have the necessary "Imports System.Collections.Generic" reference in the file so I don't see why I can't convert the result set to a generic list.
I have a Generic.List(Of ImportedVehicle) - ImportedVehicle being a simple class as below.There is an enum property which is marked as public.When I serialize to XML using an XMLSerializer, the enum's value is just set to it's default value (which is NotAllocated) and doesn't actually represent the value that is set in code.[code]
View 1 Repliesi have issue returning a list in a web method. here is the code
<WebMethod()> _
Public Function getTags(para_parents As String) As List(Of getTypeDetailsByParentName_Result)()
Dim context As New PPEntities
[code]....
the error is
Value of type 'System.Collections.Generic.List(Of SaftyonRoad.getTypeDetailsByParentName_Result)' cannot be converted to '1-dimensional array of System.Collections.Generic.List(Of SaftyonRoad.getTypeDetailsByParentName_Result)'
We are currently converting a larger legacy application from .Net1.1 to .Net2.0, both VB. Our new standard is Generic List, instead of arrays.We are recoding component by component. And while not everything is yet stored in generic.list we end up with compile time errors.Converting from generic.list to array is supported with myGenList.ToArray().But from array to generic list isnt that easy."Value of type '1-dimensional array of something' cannot be convertet to 'System.Collection.Generic.List(of something)"I know for sertain that the array consist of the type 'something', so an runtime exception converting is ok.Is there a good way to do the workaround untill the hole application is recoded?
View 1 Replieshow to convert a list of int to byte array in C#, but can't get syntax to work out for me in vb.Converting a list of ints to a byte array.
View 1 RepliesI'm writing a program that reads a directory of xml files (not well-formed), parses the xml, and dumps the data into an Excel Workbook.The file contents are similar in that they have many common xml nodes/attributes.Some files have additional nodes/attributes.The xml in these files represent configuration settings for a Web Application, one file per user.The expected output is a worksheet with a column for each node/attribute combination and a row of node/attribute values for each user.I'm just about finished with the program, but I've run into a bit of a snag.As the final step in the process, I need to loop through a generic list of array objects (that represent a user row) and send the array elements to Excel.I don't know the correct syntax to get the array objects out of the list and have been unable to find sample code specific to generic lists of array objects.[code]
View 3 RepliesIs there any difference? I mean, does the compiler care or is/are there any performance/code advantages in using one over the other?
View 1 RepliesI want to loop through all the items in the items, but first I must to cast to appropriate type which I fail. [code]
View 1 RepliesI want to pass a List of T where T is an object I've created that has about ten properties (strings, dates and integers).The lst passes to the function successfully. I am also passing an New T of the Object (itm as T).I can see all the values (see image below), but because it's generic I cannot seem to retrieve the property values and I cannot figure out how to iterate through the properties of each itm as they are retrieved in the For Each.[code]
View 10 RepliesI am trying to create a list of a generic type in vb.net 2.0 framework.
This is the generic type definition:
Public Class GenericParamMap(Of T)
Public Sub New(ByVal pParamName As String, ByVal pPropValue As T)
mParamName = pParamName
[Code]....
The compiler does not allow a "T" in the method's parameter because it's not defined, but I'm not sure how or where to define it. I thought it was okay to have a generic method definition.
I'm converting a user generated list box to an array and then generating a user defined number of random strings and placing it in a textbox.The code I have works fine as it will generate the number of random strings the user wants, except sometimes a line is blank at the top of the list but is counted as a string.
View 4 RepliesI'm looping all the properties in an object via reflection:
For Each p As PropertyInfo In values.[GetType]().GetProperties()
If p.CanRead Then
'Do stuff
End If
Next
how to determine whether the property in question is a generic List(Of T)? If it is I need to loop the list itself.
I've experimented with GetType and TypeOf but have not managed to get anything working.
To clarify, I want to keep this generic. I do not want to specify the type of T, I need to loop the list items and call the ToString method on each item. T could be one of a number of different types (application specific reference types). Is it possible to do this without specifying types?
(VB.NET 2005 with .Net 2.0)
Public Class notifierMain
Public Class Contacts
Inherits List(Of row)
Public Sub New()
[code]....
When I debug this winforms application I get curType = "notifier.notifierMain+Contacts+row" I want to the Validate function to know it is in MyContacts. How do I do this?
it seems always at this time I cant figure out how to do something maybe it has something to do with lunchtime.
Im having trouble using a method that is defined by an outside company
This is a link to their integration guide:
[URL]
This is their documentation for the class Im trying to use
OrderQueryWebService Class
This class is for SID in particular and is made for use with the notification methods. This is for the Order Query Web Service specifically, allowing clients to return the status of transactions for their merchant, whenever they want to.
Methods
/ <summary>
/ Pass through the variables required and receive a list of Transaction
objects showing transaction status
[Code].....
The MerchantCode, the MerchantUsername, the MerchantPassword are all good the List is a custom type called SetComHash.Transaction
Everytime I try adding a string to the list such as the transactionNumber and some other values it gives me a type error:
"Value of type string cannot be converted to 'SetcomHash.Transaction'
I want to reading in a excel file and extract the sCodenumber sDescription ans the sStatus and store them in a array : StatusComposeArray(5200) As MyCompose. After this I need this array for comparing outside this class. But as can you see the array is defined inside the sub: ReadingIn_ExcelFilesCompose [Code]
View 2 RepliesI have 3 similar functions, that only change based on numeric type:
<Extension()> _
Public Function ToNullableShort(ByVal str As String) As Short?
Dim intReturn As Short
[Code].....
I was trying to make a generic function out of this, but couldn't do it. How can I make a generic function that will take a specific T and make it a Nullable(of T)?
I wrote my own database handling code (actually, I write T4 text templating files that generate my database code for me) and part of it takes care of converting values from a database (as Objects) to the desired types.
I have been using this generic function successfully:
vb.net
Public Overridable Function ConvertType(Of T)(value As Object) As T
Try
Return If(value IsNot Nothing AndAlso value <> DBNull.Value, DirectCast(value, T), Nothing)
[Code]....
Simple enough, but it doesn't work... The return type of the function is (and must be) T, so I cannot return a Boolean because a Boolean cannot be converted to T!
Well... It can in this case, because I specifically check that T is Boolean, but the compiler doesn't know this so it doesn't allow me to return a Boolean. I cannot cast the boolean to T either.
I wrote my own database handling code (actually, I write T4 text templating files that generate my database code for me) and part of it takes care of converting values from a database (as Objects) to the desired types. I have been using this generic function successfully:
vb.net
Public Overridable Function ConvertType(Of T)(value As Object) As T
Try
[code].....
I am creating a 'generic input dialog': InputDialog(Of T).The idea is that I can create new instances of this dialog for different values of T. For example,I can create an InputDialog(Of String) and it displays a textbox.I create an InputDialog(Of Boolean) and it displays two radiobuttons (I could use a Checkbox, irrelevant).I create an InputDialog(Of Date) and it shows a DateTimePicker.
I do this by simply checking the type of T at run-time.In this way it is not really generic, as the dialog still has to know which type T is (which is usually not the case), but the generic is in the fact that the T can be multiple types that require a TextBox. For example, InputDialog(Of String), (Of Integer), (Of Single), (Of Double), etc, all simply display a TextBox (and it is validated later),so I still want to use generics as much as possible.Anyway, the result of the dialog is of course a property of type T. This property needs to return the value in the textbox, converted from string to T, OR the value in the DateTimePicker, converted from Date to T,OR the checked property of the 'Yes' radiobutton, converted from Boolean to T.In order to convert from any object to T I googled and found this
vb.net
Imports System.ComponentModel Public Class GenericTypeConverter Public Shared Function FromObject(Of T)(ByVal value As Object) As T Dim tc As TypeConverter = TypeDescriptor.GetConverter(GetType(T)) Return CType(tc.ConvertFrom(value), T) End Function End Class
I have to use this, I cannot simply CType a string to T since a String cannot be converted to any type T.So, my Result property looks like this at the moment:
vb.net
Public ReadOnly Property Result()[code].....
This actually works for Strings, Integers, Doubles, Singles, etc. I pass it the String in the textbox and it converts it to 'T'(note: T is then a String, Integer or Double!) just fine.So, it can convert a String to a String, Integer or Double without any problems (I am validating the text before using the Result property so it will always be a valid integer, double, etc).However, it does not work for a Boolean, nor for a DateTime. When I try that, it says "BooleanConverter cannot convert from System.Boolean" or "DateTimeConverter cannot convert from DateTime". I realize it is a bit of a strange thing, since the object already IS a Boolean or a Date(Time) so no conversion should be done at all, but this doesn't work in design-time because I need to return the objects as type T.I know that T will be Boolean when the value to be converted is a Boolean, and that T will be DateTime when the value to be converted is a DateTime, but the designer does not accept a simple CType. As I said, it does not accept this:
Return CType(rbYes.Checked, T)
because 'Boolean cannot be converted to T'.
However, I did find a way to make it work, but it seems like a complete hack... I can assign the boolean to an Object and then convert that using CType:
Dim obj As Object
obj = rbYes.Checked
Return CType(obj, T)
This works, it's accepted during design-time, and it works during run-time, but it seems very wrong... Is there no better way to handle this?
What would be the fastest way to sort a list that contains a list of objects, based upon another list? An example follows:Say I have multiple lists of employees. Each individual list has a common property value, say "Department". So I have a list of employees, in one list they all have the department string value of "Sales". In another list all the objects have a department value of "Finance". These lists of employees are then contained in a list which holds them all.
I have a second list, which should drives the sort order of the employee lists. The second list simply contains a list of strings like, "Finance", "Sales", "IT" and so on. I'd like my lists of customers to be sorted in the order of "Finance", "Sales", etc.I'm using VB.NET in .NET 2.0
I have a program that will compare an array of grocery list items glist and an array of coupon item clist.When I compare the two and if there is a match somewhere in the array I want to have a picturebox visible.When there is no match, I want the picture box not to be visible. [code] The code seems to work great until I come to the else statement.When the code finds a match it displays the picture box and the msgbox without error, but as soon as the message box is cleared, even though i've input it as an ELSE statement, the picturebox goes false again.Does anyone have any idea of how I can "hold" the picturebox to stay visible while the match between the arrays exists?
View 18 RepliesI found a code example online that purports to count the number of pages in a PDF file. However, I'm getting the error 'ToArray is not a member of 'String' on the following line:
Dim pdfMagicNumber() As Char = "0000".ToArray
I'm running VS 2010 on a Framework 2.0 project, on a machine running Windows 7 and IIS 7. I found one article that talked about IIS configuration as the culprit for this error, but my settings seem to be consistent with what they recommended.
Dim x = GetType(List(Of )) 'valid statement
Dim list As New List(Of String)
Now I want to see if list is a List(Of T) variable: Dim isList = TypeOf list Is List(Of ) On the last line I get a compile error: "Type Expected". Is there any cheap-performance TypeOf operator alternative for generics?
I have converted c# .cs to vb:= I have 6 errors on:
Red "List" says Too few type arguments to system.Collections.Generic.List(Of T)'
Orange "Calendar" says Value of type 'System.Windows.Forms.Control.ControlCollection' cannot be converted to 'Form1.Kobush.Windows.Forms.Appointment'.
[code]....
Imports System.IO
Imports System.Text
Imports System.Net
[Code]....
just hoping that someone may be able to assist me to convert system.array to double() array.
Declarations are as follows:
Private f_Data As System.Array
Private f_Measures() As Double
Private f_NumberOfObservations As Integer
I then 'fill' f_Data from a range in an Excel worksheet as follows:
f_Data = wsXLSData.Range(wsXLSData.Cells(1,1), wsXLSData.Cells(8, 1)).Value
This seems to work OK. Upon checking f_Data is indeed filled with 8 double type numbers.
I then try to convert this system.array to a double array as follows:
For i As Integer = 0 To f_NumberOfObservations - 1
f_Measures(i) = f_Data(i + 1, 1).value
Next
I then get an error pointing to the line ' f_Measures(i) = f_Data(i + 1, 1).value' of type MissingMemberException was unhandled by user code'
i m getting a collection of data in list's object. And from this list i want to get the maximum id.`
Dim objinfo As List(Of AlbumInfo) = objPhotos.GetPhotos_Alb_ID(Me.ModuleId, hdd_AlbID.Value)
Dim Photo_Image As String = ""
Dim str As String = Photo_Image & fu_Photo.PostedFile.FileName.Substrng(fu_Photo.PostedFile.FileName.LastIndexOf("."))
[code]....
this returns the "0"th positions id from Convert.ToString(objinfo.Item("0").Photo_Id + 1)but i want to get the last item's id.
i have list of string like this :
Dim totalPrice As New List(Of Integer)
how can i get sum of column(0) (C# or VB) ?
