I am trying to look at the next datarow in a datatable such as For Each dr in dt.rows
type = dr("Type")
type2 = dr("Type")
how can this be the next record? Of course, I would need to write an exception for the last record...
I have two datatables with similar structures that I want to make one existing row to be updated from another datatable.
For example, "tableA" has three columns: "one", "two", and "three"; with "one" being the primary key...
and "tableB" has three columns as well: "one", "two", and "three"; with "one" being the primary key.
Say there is a row on tableA that is different than a row on tableB (with a matching primary key). What I wanted to do, as efficiently as possible, is to take the that row from tableB and replace the one on tableA so it'll be modified.
I'm not sure if there's an easier way of doing that instead of using loops for setting the row's items.
I have a form with a datetimepicker. On load of the form, I set the value of the dtp from a datarow, with the following vb.net dtpRequiredDate.Value = dr.Item("RequiredDate")
This works fine. But when the form is loaded subsequent times in the session (form is not disposed on closing, shown as dialog), when presented to the user it just shows todays date, not that set by the above code. Stepping through code, the Onload code runs, and the dtp is set by the above code. Checking the value in debug at this point, the value of the dtp is correct. There is no further code in onload. But by the time it is displayed to the user shows todays date again. I have set a break point on the valuechanged of the dtp but it never fires again after it has been set by the above code.
Can anyone explain exactly why Method 1 in the following code does not alter the DataTable where the other 2 methods do? It's obviously some kind of referencing issue, but why exactly?
[Code]...
I am trying to add new operators (their name, category, password etc) to a dataset called "operators". (Though I could be adding any new datarow to it's relevent dataset). My program has allowed for the entry of all relevent data and filtered it to make sure it is acceptable. The user has pressed the UPDATE button and my program must now add the new datarow. (My code is in bold!).
I assume that I must first establish a connection to my database, so I start with :-
Dim Conn As New OleDbConnection(ConnectionString)
'I feel that something is needed here to reference OleDbDataAdapter - but what?
Conn.Open() 'Is this line needed?
Dim DSetOPERATORS As New DataSet("operators")
Dim DRowOPERATORS As DataRow = DSetOperators.Tables("operators").NewRow
[Code]....
I am trying to get data out of a DataRow. Example:
Dim dr_simslot = dsFSC.tblSimSlot.Select("SimID=" & simID)
What I want is to say something like this:
Dim temp = dr_simslot.columnname
This is because I know only one record will be in the datarow.
for each row as datarow in dt.rows
if row is last row in dt
msgbox("last row in datatable")
end if
next
how do i detect the last or first the row is in datatable
I have a master DataTable that may contain some DataRow.RowError. I create multiple subset DataTables from my master DataTable using the DataView.ToTable method whenever the user wants to apply a filter or sort to the master table. However, the ToTable method does not transfer the RowError property of the data rows in the master table to my new subset table. So in order for me to transfer the row errors from my master table to my subset table I have to use a loop. The code below works fine, but with one exception (see below code).
Dim dtMaster As DataTable = Me.ds.Tables("Current")
Dim dtSubset As DataTable
Dim dv As DataView
[Code]....
Note, the primary key may contain 2 columns, however this is a rear case. If you know of any other solutions to transfer row errors let me know. I don't have to use the Find method.
Code is in VB 2008,
In code i am using Datatable, using that select method datarow
Dim dt as New Datatable
Dim dr() as Datarow = nothing
[code].....
Public Class frmVisitor
Private dbConnection As New OleDb.OleDbConnection()
'To add a DataAdapter
[Code]....
I'm using a LINQ query to translate data inside a DataTable object to be a simple IEnumerable of a custom POCO object.
My LINQ query is:
Dim dtMessages As DataTable
'...dtMessages is instantiated ByRef in a helper data access routine... '
Dim qry = From dr As DataRow In dtMessages.Rows
[code]....
However, the compiler is throwing a warning message under dr As DataRow with the message: Option Strict On disallows implicit conversions from 'Object' to 'System.Data.DataRow'.Why am I getting this error and what do I need to do to fix it? I would have thought that dtMessages.Rows returned a collection of type DataRow. Is this not correct?
Private Function ColumnEqual(ByVal A As Object, ByVal B As Object) As Boolean
[Code]...
I've VB.NET function that reads data from an Excel sheet and adds rows in a Datatable.
Private Function LoadDataToRows(ByVal TableName As DataTable, ByVal Header As System.Collections.Specialized.StringCollection) As Boolean
Dim HeaderDataExcel As String = String.Empty 'Data Header
[Code].....
But no data was add to the table, only emty rows.
I've VB.NET function that reads data from an Excel sheet and adds rows in a Datatable.
Private Function LoadDataToRows(ByVal TableName As DataTable, ByVal Header As System.Collections.Specialized.StringCollection) As Boolean
Dim HeaderDataExcel As String = String.Empty 'Data Header
[Code].....
I have the following code where I'm trying to bind a datarow to a textbox.
Me.TierNameText.DataBindings.Add("Text", Me.m_TierRecord, "tier_name") Problem is, when the form is displayed no text is shown in the textbox.
This code runs before I call the form's ShowDialog method. I stepped through the code to make sure the datarow has data, and indeed it does.
I rarely use databinding but thought I'd try it this time.
setting a DataRowView equal to my DataGridViewRow.DataBoundItem, then using the DataRowView.Row property (In my code below).
Here's my code:
Dim tblTemp As New DataTable()
Dim row As Windows.Forms.DataGridViewRow
Dim rowView As DataRowView
[code]....
I have dataset like
<DATASET>
<SALES_DO_INDEPENDENT>
<SALES_DO_INDEPENDENT_ID>22</SALES_DO_INDEPENDENT_ID>
[Code]......
I have a DataGridView that is bound to a DataTable thru the code. I want to be able to modify the data when a row is selected from the Grid. How do I reference that row of data from the grid so I can convert it into the DataTable row to be updated? I'm trying to do something like this:
Dim row as DataGridViewRow = DirectCast(dgvAddress.CurrentRow, DataRow)
This isn't working. I'm getting an error basically stating that I can't convert a DataGridViewRow into a System.Data.DataRow.
[code].....
I have a combobox that pulls a list of values from a database. When a new entry is entered I want an entry in the combobox to read "New record". However, from what I have seen I can only insert and object, such as a DataRow, into the combobox. Is there anyway I can convert a string to to a DataRow, or some other object and insert it in to the combobox? I know there is I am just rusty on my vb.
View 3 RepliesI am having an issue with a DataRow not being updated in my DataTable. The trouble is my value is not being changed in the row.I have done a simple example which shows what I am trying to achieve. My row does not change values...ever...and no errors are found
Dim cm As New DataTable
cm.Columns.Add("Name")
cm.Rows.Add("Craig")
[code].....
I am using VB 2008 and Access DataBase. My code need to store original data values for row being updated to compare it with new values later. For this to accomplish I wrote following
Dim dRowOriginalRow
As DSetPurchaseSale.PurchasesRow
Private
Sub btnEdit_Click(ByVal
sender As System.Object,
[Code] .....
When I am running this code, i am not getting the original values in dRowOriginalRow variable insted it is also updating with new changes made in controls, so the dRowOriginalRow and dRowModifiedRow are always same. Again may I use Equal To sigh to compare both rows as I did in my code?
True : dtPurchaseDate.Focus()
i have a list of datarows. each row is having mutiple columns like userid,date,flag,etc.i want to sort the based on date. how can i do that ?
my code is:
Dim
listOfRows As
New List(Of
DataRow)()
[code]....
i want to sort the listOfRows in ascending order of date which is a column in a row?
I do the following:
Dim rw() as exportDataset.vendorPricingRow = ExportDataset.vendorPricing.Select("field1 = 1")
I am converting data table content to string, Say the dataset has 12 rows and 8 column.
At the end, the Dict contain 12 rows or 96 columns. what's wrong with my code below, how do I reset the row?
Dim ds As DataSet = ClsDB.GetDataSet(sql)
If Not ds Is Nothing AndAlso ds.Tables.Count > 0 Then
Dim row As New List(Of KeyValuePair(Of String, String))
[CODE]...
I am having trouble setting a datetime column in a datarow to null or MinValue and updating the database row using a DataAdapter update command.In one scenario, if the value in a text box is not a valid data, I set the value in the datarow = DateTime.MinValue. The value returned by MinValue is #12:00:00 AM#. An error is thrown on the Update command "SqlDateTime overflow.Must be between 1/1/1753 12:00:00 AM and 12/31/9999 11:59:59 PM."
In another scenario, an error is not thrown but the DateTime value on the row is not changed.The database column allows nulls and I can set the value to null using a SQL update command.
If a field called X in a datarow called R is an int32 and Y is an int32 how can I make this statement work:
r!x += y with option strict on.
Error 8 Option Strict On prohibits operands of type Object for operator '+'.
If a field called X in a datarow called R is an int32 and Y is an int32 how can I make this statement work:
r!x += y
with option strict on.
Error 8 Option Strict On prohibits operands of type Object for operator '+'.
Is it possible to pass a DataRow as a parameter to a sub?The following example will (hopefully) make clear what I want to do.
Code:
myDataAdapter.Fill(myDataSet)
For Each myDataRow In myDataSet.Tables.Item(0).Rows
MySub(myDataRow)
Next
And the sub:
Code:
Private Sub MySub(ByVal drData As DataRow)
End Sub
I get an error at design time: Error 2 Expression does not produce a value.
I am working in vb2008. Is there a simple way to clone the contents of a datarow in a datatable into a new datarow instance that can be added elsewhere in the table. Can I create a new instance of a datarow and set it equal to an existing datarow?
View 5 RepliesHow do I find out in code the byte size of say a DataRow object or any object for that matter.
View 1 Replies