I need to query an array. I have tried to use LINQ but with no success.
Here is a simplified structure of Insurance
Public Class Insurance
Public _typ As String
Public _numb As Number()
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how can i query 2 arrays simultaneously?for example:
dim string1() as string = {"a","b","c"}
dim string2() as string = {"d","e","f"}
dim string3() as string = ? 'linq query that selects all elements in string1 + all elements in string2
Basically I have the follwing:Dim ctx As New AdminCoreEntities Dim roles = (From r In ctx.Roles where r.Name.StartsWith("cust") Select r) 'list of System .Linq.IQueryable(Of AdminCoreModel.Role)
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The error i get when i run this is: Unable to cast object of type System.Data.Objects.ObjectQuery`1[AdminCoreModel.Role] to type AdminCoreModel.Role
Basically I have a many to many situation and I try to get all the Quicklinks objects queried by their roles and not quite sure why EF will cast to a single AdminCoreModel.Role when i.Roles is a collections of objects.
How do I order by and group by in a Linq query?I tried..Dim iPerson = From lqPersons In objPersons Where Len(lqPersons.Person) > 0 Group lqPersons By key = lqPersons.Name Into Group Order By Group descending Select Group, key
For Each i In iPerson
tmp = tmp & vbNewLine & i.key & ", " & i.Group.Count
Next
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I have a query that 'selects' object of a type:
Dim l as IList(Of Foo) = (From dataRow As DataRow In table.Select()
Where CStr(dataRow("Column1")) = "A"
Select New Foo(CStr(dataRow("Column1")), _
CStr(dataRow("Column2")))).ToList()
What's happening is that if i set a break-point to the constructor of Foo and step, the constructor is hit and the parameters are loaded with the arguments. However, l has empty Foo objects (the members in every object are Nothing). What could be happening here?
I am creating a mediaplayer / playlist creator tool that basically imports MP3 songs into playlists (grids). I'm looking to add search functionality where the user can search all open playlists (or a subset of the open playlists). A Playlist is basically a collection of AudioFiles, where an AudioFile is a class that holds the filename of the MP3 file and then exposes the tags (Title, Artist, Album, etc) in public properties.
The idea is that the user can search for a certain expression (for example "the"), and that he can then choose whether to search in the title, in the title and artist, in the title or artist, in the title, artist and/or album, etc. However, I'm having a hard time implementing this and also having it kind of dynamic.
At the moment I am simply gathering all the AudioFiles from the open playlists (or from the subset of playlists the user chooses) and then running a simple LINQ query to find those AudioFiles where the Title contains the search text. Then I display the resulting AudioFiles in a new playlist window:
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In case the AND / OR distinguishing is too hard, I would be happy to start with just letting it default to 'OR', so that the user can check Title and Album for example. If he would then search for 'a' then all songs that contain 'a' in their title as well as all songs that contain 'a' in their album should be returned. I guess that makes it easier, but I still wouldn't know how to dynamically create the LINQ query.
from a list, which got 3 attributesI want to return a new list of that class where attribut1 recurrence in the list equals Xfor an example this;
1,a,b
1,c,d
1,e,f
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I have an array of unknown (to the current method) class objects. I do know that each class has a property called "Number". I am trying to write a LINQ query where I am looking for the object with the next Number in sequence. AKA, I'm at Number 8, use a LINQ query to find the object where Number=9.
View 5 RepliesI am using VB .Net for this, so I don't have access to var or this would be a simple matter.Right now my query is as follows
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So I used this query in LinqPad to help me determine what the object would look like. I got back a IOrderQueryable(Of RSError) which then contained a IGrouping(Of String, RSError) for each grouped collection of objects returned by the query.However I ended up with the current object type of errors as IOrderedQueryable(Of IGrouping(Of String, RSError)) because of the cast error I am getting in VS.
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I'm not sure how to get rid of the VB$AnonymousType_1 Part of the returned object.Am I even on the right track here or am I missing something completely?
I have a the following Class structure. Company > List(of Departments) > List(of Employees) I want to Query a Company to find out if it has a department of the following name and a Employee in that department with the following ID! How could I query this. The way I have the code it expect to return one department so I have it doing
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Is there any particular reason why creating a reference to an object in an IEnumerable Linq query would be really slow? I have a Linq query list consisting of my own objects (count is about 200).I was doing a time-critical task, and this line (which was used a lot in a loop) took nearly a millisecond to execute:
Dim CurObject as MyClass = QueryResult(CurIndex)
I have the following xml document which would be taken from the web and stored into an XDocument object.
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I have these objects:[code]Using LINQ I need to take a List(Of MakeInfo) and a List(Of ModelInfo) and aggregate the StockInfo from ModelInfo into the List(Of MakeInfo).So for each MakeInfo I will have a total count of all stock where MakeInfo.Name = ModelInfo.Make, and also a minimum price.I think it's going to be something like this, but I'm having trouble accessing the nested object and not sure if it's going to be possible with a single query.[code]
View 2 RepliesI have 2 classes
Public Class Shipper
Public Property ShipperID As Long
Public Property CreateDate As DateTime
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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 want to let the user input objects to a richtextbox 1 object on each line, and somehow use Random.Next to select pseudorandomly a few objects, the number 'few' inputted in a textbox.
View 9 RepliesWhat is the VB.NET syntax for declaring the size of an array of objects at runtime?To get an idea of what I mean, here is the code so far:
Private PipeServerThread As Thread()
Public Sub StartPipeServer(NumberOfThreads As Integer)' ??? equivalent of C#
' ??? PipeServerThread = new Thread[numberOfThreads];
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given this function:
Public Function Search(ByVal StartIndex As Integer, _
ByVal MaxResults As Integer, _
ByVal AccountNumber As String, _
ByVal LastName As String, _
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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 the read the article "Creating Control Arrays in Visual Basic .NET" (link: [URL]) and I its very good and useful code for 1D array of objects. What if someone wants to make a 2D array of control objects. For example creating a "table" of 8x8 buttons that will be able to change properties by using the arrays x-y coordinates. Something like button(x,y). backcolor.black or similar.
View 3 RepliesI have to join two main tables, and I need to filter the results by elements in an ASP.NET web form. These filters are created on the fly so I have to use a lot of where extensions to filter the query. I want to execute the query with as optimized SQL as possible.
I am first doing a simple join between TW_Sites and TW_Investigators. Then there are two sub-tables that are involved. TW_InvestigatorToArea and TW_InvestigatorToDisease. While most of the where clauses are working fine, I have found a performance issue that won't be an issue right now, but will be an issue as the table gets bigger.
The arrays DiseaseCategories and DiseaseAreas would be the results of a CheckBoxList result.
Protected Sub LoadResults()
'Get Dictionary of Filters
Dim FilterDictionary As OrderedDictionary = Session.Item("InvestigatorFilterDictionary")
' Initialize LinqToSql
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In C#, one can create an array of anonymous objects with new []. This was not supported in earlier versions of VB.NET, but a comment by Chris Dwyer in another StackOverflow post suggests to me that it might be supported in VB.NET 2010. I haven't been able to confirm this though.
View 1 RepliesWith the following code, I'd expect to get the array elements back that I put in. Instead, the last array element, is output three times.e workaround would be to dimension the array explicitly to hold four strings, but I used this contruct all over my VBA code and I'd rather know why it doesn't do what I expect.
Sub test_d()
Dim youvegotitems(100) As Object
Dim v(4) As String
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This probably sounds daft, but im struggling to get to grips with Classes/Modules/arrays and objects, as well as there uses and what they are, and yes im still coding some how i hear you cry.The reason i ask is because Ive got a load of Dim's in my program that are the same giving locations of files and folders and wondered can they be used as a module that i can alter after the program is built, incase of folder locations being wrong or moved, manually correct after install.
View 1 Repliesim trying to make picture boxes as arraybox(0)box(1)ecti want it to be an array so i can make infinite of them
View 15 RepliesForgive 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."
I have a VB.NET application and use some third party (closed source) ActiveX controls. One of the controls represents a "camera" (connected over several interfaces) and I try to write an example how to work with several cameras in one application. To do this I allocate multiple "camera" objects dynamically as an array which works as expected like this:
Const NUM_CAMERAS = 2
Private MyCameras(NUM_CAMERAS ) As xxx.MCamera
But the camera objects needs to be allocated with WithEvents because they raise events when a new image was taken. I found out that WithEvents variables cannot be typed as arrays and this is a pretty common problem so I also found some workarounds: [URL]. This is already pretty good and I adopted this to my concept. So I have a MyCameras array and a MyCamera all "without Events", first allocate a new MyCamera object, add a event handler and then put it into the array.
Unfortunately I get an error when calling
AddHandler Camera.ProcessModifiedImage, AddressOf MyHook
Normally "MyHook" is declared as
Private Sub MyHook (ByVal sender As Object, ByVal ModifiedBuffer As xxx.ProcessModifiedImageEvent) Handles Camera.ProcessModifiedImage
Like in the "Button examples" I just removed the "Handles Camera.ProcessModifiedImage" but I get an error that "MyHook" has not the same signature as the Delegate
Delegate Sub ICameraEvents_ProcessModifiedImageEventHandler(ImageIndex as Integer)
I want to extract large amounts of data from Excel, manipulate it and put it back. I have found the best way to do this is to extract the data from an Excel Range in to a large array, change the contents on the array and write it back to the Excel Range.I am now rewriting the application using VB.NET 2008/2010 and wish to take advantage of any new features.
Currently I have to loop through the contents of the array to find elements with certain values; also sorting large arrays is cumbersome. I am looking to use the new features, including LINQ to manipulate the data in my array.Does anybody have any advice on the easiest ways to filter / query, sort etc. data in a large array. Also what are the reasonable limits to the size of the array?
Problem in VisualBasic 10 on Windows 7 OS I have a form which has 30 lines for user input in format <textbox for Name> <comboBox for Type> <comboBox for Quality> <NumericUpDown for Amount> At the start of each line is a CheckBox. The intention is this enables/Disables the line. I have associated each object with an Array - eg
Dim Name(30) As Textbox
etc
and assigned
Name(1)=Name1
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ie enable/disable the boxes on a line dependent on whether CheckBox is Checked The Sub for Picked_Changed refuses to allow referenced to the arrays within, even if not generated by the picking of box (see above - it allowed '=Men3.Value' but not 'Men(3).Value', although the button sub is fine with this)
I used the tool about 3 years ago to create the classes for a webservice client to send or recieve arrays as complex data. Now i have to update these classes, since there are additional informations, that have to be exchanged. When i use the tool now with the new wsdl-files, it does'nt create the classes for complex data (structur, IGCTMObjectFactory), but only one class for simple data. In addition i have to establish a new client, that sends an array of complex data and receives another array of complex data. I tried to build the classes manually combining the client that sends an array with the client, that receives an array, but I failed.
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