I deal with a lot of XML for transformations. I typically find that I spend most of my time doing something like this[code]...
I suppose that is okay, but I'm just wondering if there is some better way of handling this where I Dim the element or attribute and then start processing for my transformation, if the element is not there it will just silently and gracefully fail and move on to the next thing in my code.
Does anyone know what "IsNot Nothing" and "TryCast" means in code?
View 2 RepliesIf Object.Value IsNot "Something" Then Can you do this, or are there certain cases in which it wouldn't work? Wasn't sure if this should only be used for integers and booleans.
View 3 RepliesI am trying to sort a list of classes, and I need the classes with a subclass that isnot nothing first in the list. I thought the following would work but it doesnt.ListOfClasses.Sort(Function(x, y) If(x.SubClass IsNot Nothing, 1, 0)
View 3 RepliesI am using this code bellow to read each line of a file doing stuff then repeat to the end in a while loop. My problem starts after that since I have to exit this loop then go back to it and start the process all over again 100+ times and I cant go back in since it knows I hit "Nothing" or EOF. Is there a way to do this without opening and closing the record 100+ times??
vb
inputRecord1 = inStreamReader1.ReadLine()
While (inputRecord1 IsNot Nothing)
First post here so Im sorry if im posting in the wrong place. Im trying to build a simple poker game which requires the program to recognise hands of each players. Luckily there are 3rd party solutions such as pokereval. However my problem comes when i try to convert a C# ported version of pokereval by Keith Rule, into vb.net. The following error shows up referring to the line with the *.
[Code]...
How can I convert this code LINQ to SQL in C # LINQ to SQL in Vb.net
[Code]...
I'm trying to write this as LINQ, [code]I'm a LINQ beginner, so far I'm not quite sure where to use and where not to. If in this case LINQ will do more harm then help, feel free to flame me.You can assume that there is an overload for AddLink() which takes IEnumerable
View 2 RepliesI only want to return a certain number of rows into the DataTable via LINQ's Take or use it on the Rows property, but I am not sure how or where to do it: Here is the current code:
Dim dt As DataTable = GetDataTable("sp", params)
For Each dr As DataRow In dt.Rows
Dim o As New OR()
[code].....
I have this code to get images width and height from header file without full loading the image..I convert it automatically from C# to VB.NET by [url]....The source C# code here:http:[url]....
Now I need this code to work with .net framework 2.The code doesn't work after converting even with .NET 3.5
Imports System.Collections.Generic
Imports System.Drawing
Imports System.IO[code]..........
I want to populate a LINQ table from code, not DataBase.Is it possible ?System.Data.Linq.Table<Question> myquestions = new System.Data.Linq.Table<Question>();
View 2 RepliesCan convert this c# code to vb.net code.
DataClassesDataContext dc =
new DataClassesDataContext();
//proc_GetExistProductDetails is a Stored procedure method from my DataContext class.
[CODE]...
I use the following code to fill the Table1 dictionary with the information found within the LINQ query.
Dim DB As New DatabaseDataContext
Dim Table1 As New Dictionary(Of String, Integer)
Dim Table2 As New Dictionary(Of String, Integer)
[code].....
I am using DataSet.ReadXml() to create a DataSet from the following XML file, so that I can quickly query it using Linq.[URL]..I then use the following object to create a DataTable which can be used as a dictionary, with a ConvertToFriendlyFormat function that takes an Emulator_Id and and a string that corresponds to a DicEntry node's StoredFormat attributed, and return the same node's FriendlyFormat attribute.
This does work BUT it is extremely slow (~11 seconds to call it ~220 times). I have been unable to figure out how create the DataSet when the object is initialised and just query the simple DataTable in the ConvertToFriendlyFormat call. I guess this is what is slowing it down?
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I've been trying to write this snippet of code in VB, can anyone see what is wrong with it? I am recieving an error on line 5.
Dim a1 = From rows In db.tPDMLinkUsages _
Where (rows.ACCESSDATE >= DateTime.Today.AddDays(-90)) _
Select New With _
{ _
[CODE]...
I am referencing a project so I can create a messaging system on my website. [URL] how I would replicate this function in my dal and bll so that I can get the same output. In the example they use a datacontext. I mostly return datatables in frim my DAL.
public List<MessageWithRecipient> GetMessagesByAccountID(Int32 AccountID, Int32 PageNumber, MessageFolders Folder)
{
List<MessageWithRecipient> result = new List<MessageWithRecipient>();
using(FisharooDataContext dc = conn.GetContext())
[code]....
given this function:
Public Function Search(ByVal StartIndex As Integer, _
ByVal MaxResults As Integer, _
ByVal AccountNumber As String, _
ByVal LastName As String, _
[Code]....
instead of what I expected:
Select count(*) from remitline where lastname = "smith"
What am I doing wrong building up the where clause? I'm using Castle ActiveRecord 2.1
if there is that much of a performance gain in running a LINQ stored procedure versus a LINQ query?
View 1 RepliesI have a listbox on my xaml form that I bound to a List(Of MyType) property. I populated this list like so:
Dim fields As List(Of CheckableFields) = New List(Of CheckableFields)
Using context As ITIPEntities = New ITIPEntities()
Try[code]....
Now I'm at the point where the user selects the fields they want included in a report and I need to iterate over the required fields. This is my linq query:
For Each checkedField In _requiredFields
If checkedField.IsChecked Then
If checkedField.FieldData IsNot Nothing AndAlso checkedField.FieldData.Trim IsNot String.Empty Then[code].....
Example-I have a person class
Public Class Person
Private _fname As String
Public Property Fname() As String
[Code]...
Forgive my ignorance on this.I have this LINQ Query:Dim ngBikersDataContext As New CarBikeWalkDataContext
bikersList = (From c In ngBikersDataContext.Reg_Bikers _
Order By c.L_Name _
Select New Bikers() With { _
.BikerID = c.BikerID, _
.F_Name = c.F_Name, _
[Code]...
with the error "Overload resolution failed because no accesible 'Select' accepts this number of arguments."
Over the "NEW" I get an error " ')'expected."
We are doing a query against an in-memory collection of LINQ data objects. The wrinkle is that we are ordering by a column in a related table whose records have not necessarily been loaded yet (deferred loading:)
Dim oPkgProducts = _
From b In oBillPkg.BillProducts _
Where b.Successful.GetValueOrDefault(Common.X_INDETERMINATE) = _
[code]....
The pattern I'm trying to avoid is checking if a string (normally a control's text value) is null/empty, and if it is, comparing it using Contains to a field in my data. Obviously the field isn't hard-coded into my extension, neither is the object type.What I've got works perfectly in Linq to Objects, but I get the generic run-time error "LINQ to Entities does not recognize the method 'System.String Invoke(GenericQueryHelper.Customer)' method, and this method cannot be translated into a store expression." when using an entity framework model.
Here's what I have:
<System.Runtime.CompilerServices.Extension()>
Public Function CompareAndFilter(Of T)(source As System.Linq.IQueryable(Of T), expressionField As System.Linq.Expressions.Expression(Of System.Func(Of T, String)), compareTo As String)
[code]....
I want my usage to look something like this:
Dim results = repository.Customers.CompareAndFilter(Function(c) c.FirstName, searchText)
I do need to get this running against a SQL database really, as it is filtering results, so I don't want to be doing that in memory.
How do I add ROW_NUMBER to a LINQ query or Entity? How can I convert this solution to VB.NET?
[Code]...
I'm having trouble porting that last line. I have been unable to locate a VB.NET example. I'm actually not looking for any paging functionality like the example provides, just good old-fashioned Row_Number(Order By X) row index.
How can I convert an object of type System.Data.Linq.DataQuery to System.Linq.IQueryable?I'm working with Visual Basic/Silverlight, and the source code of my query is as follows:
Public Function Get_Cli_Pag() As IQueryable(Of V_Cliente_Pagare)
Dim Qry = From P In Me.Context.Pagares Join C In Me.Context.Codigos On C.Codigo
[code]....
I just upgraded a project from VB 2008 to VB 2010. Before, the project did not use LINQ. I have started implementing it. So, I have updated the target framework from 2.0 to 3.5, and added a reference to System.Core, and imported the namespace System.LINQ to the entire project and also imported System.Data.LINQ into the form I'm working with (because it was not available in the list for Imported Namespaces in the references tab).
It's not throwing any errors now, but my IntelliSense is not working for LINQ stuff.
For example... I write this:
[CODE]....................
Then, if I type S. on the next line, the IntelliSense doesn't grab what it should for S (Only get Equals, GetHashCode, GetType, ReferenceEquals, and ToString, instead of the options I should get like Count, First, FirstOrDefault, etc...). If I Type S.First. then its the same thing, no IntelliSense that lists the available fields for S, just the standard options (Equals, GetHashCode, GetType, ReferenceEquals, and ToString). I should be seeing my column names in my table when I type S.FirstOrDefault.
So any ideas what is going on? When I type the code, for example, MessageBox.Show(S.FirstOrDefault.FirstName), it works perfectly. But it doesn't change the casing of the text (so it would read s.firstordefault.firstname) and no intellisense while doing it. But no errors. BTW - Everything works perfectly when creating a NEW VS 2010 application, it's just my projects upgraded from Visual Basic 2008 that have this issue.
I have some code to execute code at runtime...
Here is the main
Private Sub Button1_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles Button1.Click
Try
If TextBox1.Text.Trim <> "" Then
If TextBox2.Text.Trim <> "" Then
[code]....
When the button is pressed, it all works and the following files are created: yahoo.dll and yahoo.pdb My question is this: What is the code to load the already compiled yahoo files to execute the code again, without having to recompile the code?
I know that LINQ queries are deferred and only executed when the query is enumerated, but I'm having trouble figuring out exactly when that happens.Certainly in a For Each loop, the query would be enumerated.What's the rule of thumb to follow? I don't want to accidentally enumerate over my query twice if it's a huge result.
For example, does System.Linq.Enumerable.First enumerate over the whole query? I ask for performance reasons. I want to pass a LINQ result set to an ASP.NET MVC view, and I also want to pass the First element separately. Enumerating over the results twice would be painful.It would be great to turn on some kind of flag that alerts me each time a LINQ query is enumerated. That way I could catch scenarios when I accidentally enumerate twice.
I recently switched from VB to C# and have, for the most part, been able to make the transition without too much trouble. Currently I am working on converting a VB.Net program into C# and am having trouble with a couple of code blocks that include Linq.
This is one of the VB.Net lines of code that I am having trouble with:
I have tried to do the same thing in C# like this:
I am getting a compile error on the dt, which says Could not find an implementation of the query pattern for source type 'System.Data.DataTable'.'GroupBy' not found. VS also has issues with the whole into Emailers = group;
I have tried to get this right using examples from my search but have not been able to get it right.
This code was posted in Chit Chat and everyone is saying how great it is. I just have Visual Studio 2010 and no familiarity with VB6 so I thought it would be good to convert the code to Visual Basic 2010.
[Code]...