LINQ To DataSet - Convert EnumerableRowCollection Into DataTable
Mar 2, 2012
I am trying to convert my EnumerableRowCollection into a DataTable, but I can't see the CopyToDataTable method. The enm.CopyToDataTable() has the blue saw tooth line under it with error saying " 'CopyToDataTable' is not a member of 'System.Data.EnumerableRowCollection' ". I have set a Reference to System.Data, System.Data.Linq, and System.Data.DataSetExtensions. I thought the CopyToDataTable method was part of the System.Data.DataSetExtensions, right? Anyone know why I can't access this method?
When the user clicks an "Edit" button on my form, I want a box to come up which allows the user to edit a DataTable in a strongly-typed DataSet. What's the best way to do this?
I have code running in the Datatable.ColumnChanging event in my dataset. This dataset underlies a form and conventional drag/drop controls are in place for data entry.when the event triggers and runs, I am running code in the form that checks the dataset.HasChanges property. It is showing False. But this is immediately after the ColumnChanging event has been triggered.Okay, I see by others posts and MSDN that .HasChanges will only be true after moving off the row with the changed column. I have also noted lots of discussion about the advanced binding property of DataSourceUpdate Mode, but that does not address this issue.I guess I can do this by checking the state of the row for the binding source. Just seems odd that the event behind the dataset can be triggered and that does not change the dataset.HasChanges property.
I am finding difficulties to convert a datatable to a new datatable using a reference datatable. My question is confusing and I am not good at explaining things so I drew a picture (see below).I have two datatables on memory and I need to create the third datatable using the second mapping table for reference. The column names are just for example and it can't be hardcoded.
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
I have build a datatable in vb dim Booking_table as datatable Is it possible to add this datatable to a dataset or do I have to build in acces2007 and import in VB.
I have a strongly typed dataset and datatable and I am trying to do an add row. Dim newDT As New hdar.AccessRequestsDataTable Dim newRow As hdar.AccessRequestsRow = newDT.NewAccessRequestsRow newRow.Number = nextNumber newRow.RequestedByID = Me.cboUser.SelectedValue newRow.RequestedOn = Date.Now.ToShortDateString [Code] .....
I am trying to put a datatable into a dateset, which I then export to a CSV file. I am getting this error
DataTable already belongs to another DataSet. on the following line dsExport.Tables.Add(dtExport) VB Using dtExport As DataTable = DirectCast(dgvSafetyGlasses.DataSource, DataTable)
I am ably to load a XML file (via a filepath) to a datatable. See code below.However, I'd like to be able to load a in-memory XML document to a datatable.
Code: Public Function XmlToDataTable(ByRef filePath As String) As DataTable Dim ds As New DataSet Dim dt As New DataTable ds.ReadXml(filePath) dt = ds.Tables(0).Copy() Return dt End Function
I found the following example on [URL] Unfortunately, I need it in VB and it's using some constructs that neither I nor the automated code converters reciognize. Anyone out there know how this should be written in VB.Net? (the problem spot is the "select new {...")
PeopleDataSet ds = new PeopleDataSet(); using (PeopleDataContext context = new PeopleDataContext()) {
I need help converting datatable to xml using Linq. I could do it with hardcoded column names as you can see in my code .. but i need it without hardcoding it ..Example datatable ..My linq query ..
Dim xmlDoc As New XDocument( From row In dt.AsEnumerable() From row In dt.AsEnumerable()[code]......
I'm completely dense here, but I'm trying to get some stats from a DataTable. One of the columns in the datatable is called "colour".I need to find out how many of each instance of "colour" are in the datatable.
I'm trying: Dim q = From p In PGWorkingDataTable _ Group p By p("colour") Into Group _
discovered the compact mode of this instructions vs usual code. I found sample code for selecting, etc. from a datatable, transforming a column in a list or array - all operations are "Select"s - readonly.I need to make an simple update on a certain rows (using LINQ) from a DISCONNECTED datatable for which now I'm using this
for each dr as datarow in dtable.Rows dr("MyField") = 77 next
I want to create a third datatable to include records from dt1 when they are NOT in dt2 using LINQ. In this case, I can bind the third datatable to a dropdownlist.
Am new to the concept Linq.I created a var where i joined 3 tables to get the data and then bind it in a datatable and create a csv file. Now i want to use an additioanl table in the same variable to be bind with the datatable but my problem is i cant use join here since i dnt have any common col or primary col in this additional table.How do i add this extra table?
I'm writing a small web app in VB.NET and I would like to do paging for my DataTable in the following function :
Public Shared Function Testing(ByVal KeyWord As String, ByVal CurrentPage As Integer, ByVal PageSize As Integer) As DataTable Dim db As New BibleDataClassesDataContext
Currently, I am using a loop to find the row I want to update.
Public Sub pubsub_SetUserDGVColumnWidth(ByVal sender As Object, ByVal e As System.Windows.Forms.DataGridViewColumnEventArgs) ' update all user settings for the given column
I have a dataset that is populated via a SQL Stored Procedure, the format of which is below: Country | Brand | Variant | 2004 | 2005 | 2006 | 2007 | 2008 The number of rows varies between 50 and several thousand. What I'm trying to do is use Linq to interrogate the dataset (there will be several Linq queries based on user options), but a simple example would be to SUM the year columns based on Brand. I have the following that I believe creates a template for me to work with: But from here on I'm absolutely stuck!
I used to do all the database logic with SqlCommand and the Methodes ExecuteReader and ExecuteNonReader and never used something like DataSet or Datatable.
Dim dbcon As Data.Common.DbConnection Dim cmdselect = dbcon.CreateCommand() cmdselect.CommandText = "SELECT * FROM users WHERE id = 1"[code]...
This is sometimes hard to administrate. So I would like to use a more efficent way. May thought was to Query a DataTable, make changes to it and then call .AcceptChanges and all changes where wrote back to the Database. But this seems not to be the way it works?The method .Update requires that i bring with my own update command, if i have to do that myself, why using the datatable, dataset... anyway?How do you write your DB Backend?
With SQLCommands arrays and variables? With DataSet, DataTable? With a VisualStudio genereated template? With Linq?
