I am looking for sample linq code snippet which uses System.Linq.Dynamic against a datatable.
Dim entities = (From ent In dt.AsEnumerable().Where(String.Format("IsUSFederal == {0}", "true")) _
Select Description = ent("Description"), Acronym = ent("Acronym")).ToList
I am getting an error "there is no accessible Where can be called with these arguments". I have included the DynamicLinq.vb file and the application compiles fine (aside from this error). I have included Imports System.Linq.Dynamic but it doesn't appear to be working.
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."
When a user make a program in visual basic, for example, can he/she copy and use some of the code samples provided in the MSDN Library? Is one totally free to use such code in one's programs, and even allowed to sell software containing such sample code, or does one have to massively modify it so that it resembles little of the original.
I am looking for sample code for vb.net Dynamic Dashboard applications? i want the code in vb.net which will be my front end and sql will be my back end for database?
Dim objectsList as List(Of Object) = GetAllObjects() ' Filter from Objects just Persons ' Dim peopleList as List(Of Person) = ???
What is the most efficient and effective LINQ expression to do it?
EDIT
1 Dim selectedObjects As List(Of Object) = GetAllObjects()
2 Dim selectedPeople As IEnumerable(Of Person)= selectedObjects.OfType(Of Person)
3 Dim people As List(Of Person) = selectedPeople.ToList()
Error on 3:
Value of type 'System.Collections.Generic.List(Of System.Collections.Generic.IEnumerable(Of Person))' cannot be converted to 'System.Collections.Generic.List(Of Person)'.
I need to represent the following query using LINQ:
DECLARE @PurchasedInventoryItemID Int = 2 DECLARE @PurchasedInventorySectionID Int = 0 DECLARE @PurchasedInventoryItem_PurchasingCategoryID Int = 3 DECLARE @PurchasedInventorySection_PurchasingCategoryID Int = 0
[code]....
Now, I know that a query in .NET doesnt look like this, this is my test in the SQL Design Studio. Naturally VB.NET variables will be used in place of the SQL local variables.My problem is this: All of the conditions after "WHERE" are optional. In that a query might be made that uses one, some, all, or none of the conditions. V.PropertyID and V.Value can also appear any number of times.In VB.NET I can make this query easy enough by simply concatenating strings, and using a loop to append the "V.PropertyID/V.Value" conditions.I can also make a Stored Procedure in MS SQL, which is easy enough.However, I want to accomplish this using LINQ.
I have a .NET library which I know can be fairly easily linked from VS project to reference it from code. However for security reasons I want to place the DLL file in another location on the disk and reference it from code including executing methods and passing method parameters. What is the proper technique to accomplish this?
I am unsure why all of the sudden i am getting this error every time i compile and run my VB.net program running Oracle 10g. It ran fine many times but all of the sudden keeps saying this now.
I have a .NET library which I know can be fairly easily linked from VS project to reference it from code. However for security reasons I want to place the DLL file in another location on the disk and reference it from code including executing methods and passing method parameters.
I'm creating a project with an Add-on system, and I'm releasing an API so people can develop for my application (its called Levanta, its a basic Sub-OS, and i want people to be able to develop for it). I try to call a sample DLL i made to test out the system i created. Well, i CANT, because its not finding the functions entry point of the said function (its named initialize)...?
My program used to run on my system just fine until I removed some other applications. Then the proggy was giving me a runtime error. The funny thing is that once I installed visual basic 6 and added a reference to dao360.dll, or the Microsoft DAO 3.6 that the program then worked without error.
VB6 was never installed on this system before. The program worked just fine until applications were uninstalled from the system. What happened that caused the reference to stop working? Why did the program stop finding dao360.dll even though the program itself wasn't modified since vb6 wasn't installed?
I am getting "Initialization of the dynamic link library c:WINNTsystem32COMCTL32.dll failed. The process is terminating abnormally" when I tried to install a vb package in Windows NT.
GetProcAddress Function Retrieves the address of an exported function or variable from the specified dynamic-link library (DLL).Lets say I have something like this:
Dim moduleHandle As Integer = LoadLibrary("C:myDLL.dll") Dim methodName As String = "" GetProcAddress(moduleHandle, methodName) DLL should be win32 standard dll or .net dll.
How can I run the exported function if I have the address of it through GetProcAddress().If someone could supply some code it would be great.
I have a dynamic datatable, created from a database. I want to add a new row (blank), so there is an option to choose nothing in a combobx. Everything works ok without adding the new row. But when I add a new row, the combobox displays nothing. What am I missing?
Here is the code Dim DT As New DataTable DT = DS.Tables("CallStatus")
I work on representation layer . My friend work on datalyer( back end) I only get a value which is datatable type. How can i show it to crystal report.
I have a custom DropDownField for a GridView. I have to specify the DataSourceMethod property to the name of a function. I can not use a SqlDataConnector object. I want to take the name of the function (e.g.MyNamespace.MyClass.GetYears) and get the resulting object and assign it to a DropDownList data source.I know I will need to use the CallByName function
I am creating a data logger that pulls data from an existing OPC server. When the data logger is launched, I look into the OPC server and get the names of the sensors that need logging (ColumnNames() as string) . From that, I am creating a data table with columns based on the items in ColumnNames(). That part is working. What I am having problems with is adding rows to the table. When I read the values from the OPC server, I get an array of strings (values() as string) which is guaranteed to be in the same order as the ColumnNames.I have been trying to use an SqlDataAdapter with a dynamically built insert command, but it is getting extremely convoluted and ugly.Is there an way to add a data row to my table using an array of string values directly?
I have been trying the following but it returns unexpected results:
Dim xd As XDocument = _ <?xml version="1.0" encoding="utf-8"?> <root>
[code].....
The above result returns both 'element' nodes however it should only return the first where element/subelement@id=1/subsubelement@id=3 However if results.Ancestors. is used it returns the correct 'subelement' and if that line is not included it returns a single 'subsubelement' whih is also correct I don't understand why when mvoing to the 'element' it returns both (I realise both have a subelement with id=1 but I thought each further query would filter out the presvious results)?
UPDATE: Groo's answer was marked correct as it would be a good alternative. I decided to stick with the select/switch statements to avoid the performance issues of using reflection. As far as I can tell there is no way to do what I want without using Dynamic LINQ (and reflection) or a decompiler (to manually code each LINQ statement, which I am already doing by hand). Note: to make this update DropDownList16 through DropDownList20 were removed (needed the characters).Is there a way to abstract the building of a dynamic Linq to SQL query?
I am trying to build a Linq to SQL query with a dynamic where clause, based on user supplied filters. The user needs to be able to filter strings, integers, and dates using advanced options (equal, not equal, contains, starts with, etc). The user needs to be able to use these filters with as many or few columns as desired.
Dim query=Form f in BBSDb.Forms order by f.FormID Descending Select f where I want the f.FormID to be able to replace with a variable..What I mean is.. it doesn't have to f.FormID .. I may want to set f.FormName to be in descending for example using the code dynamically.. Is there anyway to achive?
I want to write a query that the "where" in the query is a string something like"
Dim query as string= "Name =xxxx and Date > 10 " Dim t = from book in doc.Descendants("books") Select _ [Name] = book..value, [Date] = book..value.... Where (query)
This is an extension of my last question which was answered, so I am starting a new thread. I have a query in LINQ that I was given to trim down the columns of a datatable. This works well, however, I need to make the LINQ query dynamic. So the query below:
Dim qColumnsIWant = From row As DataRow In inDT.AsEnumerable() _ Select _ EPN = row.Field(Of Integer)("EPNID"), _ EPNID = row.Field(Of String)("EPNNumber"), _ Ingot = row.Field(Of String)("Ingot"), _ ShopOrder = row.Field(Of String)("ShopOrder")
I have been looking into dynamic querying of datasets and the use of copytodatatable() for a project. I have seen in alot of forums that the copytodatatable functionality is unusable as it was removed. have an example of a dynamic Linq query being loaded into a datatable.
Dim q = From definition In definitionList _ Where definition.ValueDefName.Contains(criteria)[code]....
I have already looked into this answer: LINQ - dynamic WHERE clause?Unfortunately, it doesn't work for me using .net 4.0. When I attempt to pass the criteria string in it ask for a predicate. The end goal is to add any of these:
to be passed into the query depending on what checkboxes the user has selected. How can I create a dynamic where clause in linq to sql? Is there new syntax for passing in a where clause as a string?
