Asp.net - Looping Through Records From One DataTable And Populating Another DataTable In .net
Aug 10, 2011
I have an asp.net application where I have a datatable ("DataTableA") that returns just one column ("ProductID").
I want to read each row of "ProductID", process some business logic, then copy both those columns (ProductID & ProductIDBusinessLogicValue) to DataTableB. This DataTableB is then displayed on the asp.net page.
What would bhe the best way to read each row of DataTableA ?
When my application loops through the first code block below, I get valid data for all datarow fields. [code]...
But I get an error when looping through that code block "Collection was modified; enumeration operation might not execute." [code]...
However, in the second code block, I get a valid record for MgrID, but I get a blank value for the other fields. When I look in the database, all fields in that table have valid values.
I am trying to use the Select on a datatable and am having some trouble. I got it to find a match on rows in a datatable I fill with data in multiple columns. But I cannot seem to loop through the results to do something with it. Here is my code below. The table is already filled with data.
Is there a way of merging (importing or whatver is the correct terminology is) the data from an Array in to a DataTable woithout looping. I already know how to loop through the array to populate the DataTable with new DataRow but I'm looking for something much faster if it exists. I've got a 1 dimensional String array i.e. 'String()' that I need to populate a DataTable with new DataRows.
I have a DataTable with multiple columns including AccountNumber, Year, and Month. I am exporting the information in this table to an Excel workbook. Since this table has the potential to be extremely large, I must check the number of records in the table (since Excel can only have 65536 rows or something like that. If the original table is small enough, I need to put all of the records in a single worksheet. If there are too many records for one worksheet, I need to separate the records into multiple worksheets based on AccountNumber. Additionally, if there are too many records for a specific AccountNumber then I need to split that AccountNumber into multiple worksheets based on Year.ng:
Worksheet Name ---- Number of Records 1111 ---- 150,000 2222 ---- 50,000
I have a datatable and I apply a filter to the defaultview.rowfilter property of that datatable. If I then loop through the rows collection of the datatable, will I only be able to see those rows that the filter applies to, or will it loop through all the rows?
I am working on a project that takes an xml schema and xml data files and places them into a DataTable, the 2 files are generated from a working table that i have written to disk. I wish to load these 2 files into a DataTable. Here is What i have
vb.net Friend Function CreateTable(ByVal tableName As String) As Boolean Dim table As New DataTable(tableName) table.ReadXmlSchema(tableName & ".xsd")
[code]....
this however produces the following error on line 3
Quote:
System.ArgumentException was unhandled Message=DataTable 'get_item_list' does not match to any DataTable in source.
get_item_list is the parameter passed into this function (tableName)
I have a datagridview bound to a datatable setting its datasource property to the datatable. I would like to have a child form that contains a list of columns associated with the datatable that contains a checkbox that will allow the user to hide and show the columns ( I do not know the best control to use here) (I assume this is the easy part as All i need to do is loop through each of the datatable's columns to get the column name)
now I would like save these visible columns on some event like form_closing so that the next time the user opens the form up it will remember the settings
I came across a problem with using a BindingSource as my DataGridViews.DataSource. Whenever I applied a filter to a column in the BindingSource and the user makes changes that don't match the column filter the DataGridViewRows would automatically disappear. A similar thing would happen when applying a Sort to a column. If the user made any changes the DridGirdViewRows would automatically sort causing rows to be moved around. This was not ideal for my application and there isn't anyway to stop this from happening with the BindingSource.
To correct this issue I have to use subsets of data. I use a DataView to apply the filter and sort to the main DataTable, which creates the subset DataTable.The problem is when I use the DataView.ToTable method I loose the Primary Key and RowError information. So I have to reapply this information everytime the user filters or sorts the DataGridView.Is there a better way to get a subset DataTable?[code]...
I have a datatable that has a resource in one field and hours used in another, it looks like this -
Resource Hours Used Manager 1 Accountant 1 Field Staff 2 Accountant 3 Manager 4 Manager 1 Administrator 6 Field Staff 4 Manager 0.5 Administrator 1
What I want to do is be able to create a summary of the data table above that groups multiple occurrences of a resource and adds up the hours used for that resource, creating a summary that looks like this -
Resource Hours Used Manager 6.5 Accountant 4 Field Staff 6 Administrator 7
I am building a custom search control in VB.NET and came across a problem getting distinct records into my datagridview. I want to bring exact matches back first so I run 2 of the same query on the same table with a slight difference:
select ... like "code%" select ... like "%code%"
I have a datatable that I need to get distinct records from; I am append records from a sql query to the end of the datatable so I cannot use a union in sql to return the dataset (I want to preserve the order which the rows are added) I have been using this which is working fine for 2 fields:
But when I have 3 (or more) fields I get duplicates ONLY for the row I am querying:
dt2 = dt.DefaultView.ToTable(True, "Code", "Name", "Initial") select ... like "initial%" select ... like "%intial%"
I am clearing the datagridview.source before rebuilding this. Is there a way to get the distinct rows this way or should I just build something myself to remove the duplicates from the second datatable before appending them to the new table?
I want to create a sub that gets changes from my typed dataset and datatable. But it says mydatatable is not a public member of dataset. Passing in as objects.
Public Sub GetRateChanges(ByVal myDataSet, ByVal myDataTable) If myDataSet.HasChanges(DataRowState.Modified Or DataRowState.Added) Then ' Create DataSet variable. Dim xDataSet As DataSet
[CODE]...
Another question. . I pull this infor from a view via tableadapter and it comes from several different tables.. How could I save my changes and insert the new records to the appropriate tables>?
I am trying to go through a datatable and sort records that fall within a certain criteria, one being distance.I have a function that will get the distance between two points based on Lon/Lat and my records in table have Lon/Lat Values
exisitng code
Dim dtrow As DataRow Dim lat As Double = CDbl(34.213209) Dim lon As Double = CDbl(-118.629276)
[code]....
I can I now use the function to filter records in table that are with a certain distance?
Is there a simple way to assign a populated datatable's columns to another empty datatable? That is, I want to copy a datatable's structure only but not its data.
I'm using vb.net 2010.I have a DataSet with a Table and data. MyDataSet1 which contains Table1 I want to create another table that is the same as the Table1 but without data, but it should have the columns, etc.
Now, I want to place the rows from foundrows into an empty data table.I did what I thought was the obvious but that only returns a bunch of rows with no data
I am trying to add NewRow to the database by using datatable in dataset, but before I do that I want to make sure that row is not already there. I create new row for the datatable I am working with, fill it with information. I fill datatable with the row from database that has the same primary key as my NewRow by using tableadapter.fill method, but when I do that my NewRow that was never added to the datatable is filled with information from database(and not information that I assigned to it). I count rows in my datatable before I fill it and it's 0, so why is my NewRow affected by Fill command? (I am using VB.NET 2005 Framework 2.0)
I'm trying to copy one row from DataTable to another, I looked almost everywhere and I can't find a reason why this is happening, I'm using ImportRow and still the New DataTable is empty. Here's one of the answers similar I found and It's still not working!:
Dim newTable As New DataTable Dim dsFrom As New DataTable For Each DBShoes In list Dim iShoeID As Integer
I am updating a data table (dt_report_crypt) from an encrypted csv file in the code below:I decrypt the colums and update the same dreport_crypt, such that it will contain de-crypted data.This part is working wellI however need to use this de-crypted datatable as a data source to update a second table(dt_report), using the sql SELECT command to filter relevant data,
Dim dt_report As DataTable Dim dt_report_crypt As DataTable Using cn As
An in-line table valued function in SSMS takes about 6 seconds to return 11088 records. The same function in VB .Net 4.0 using TableAdapters.InputTableAdapter.GetData (Created with data set designer) takes about 15 minutes complete.Both are executed from the same workstation.Why does this discrepancy exist?
I have a session which contains a datatable and also have a function which returns a datatable. I need to add these two. How can I do this? The below code is to be replaced with correct code.
Session("Table")=Session("Table")+obj.GetCustomer() where obj is an object of the business layer.
The '+' sign cannot be used to add these two, so how can I do this?
