Synchronize Datatable And DataView For Read / Write Operations?

May 5, 2010

I have application in .net 2.0 in which I have a DataTable object globally in my application and have different dataviews in whole application.

When an action performed i have create many threads lets say 5 in which data is read from different dataview, meanwhile while 2/3 threads are reading data(not all 2 more left to read data) a thread write data in datatable. So we get exceptions like "Enumeration update" or "parameter not null" type.

I have use ReadWriteLock for this but do not find any luck it gets stop on ReaderWriterLock.AcquireWriterLock().

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[Code]...

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Jan 3, 2012

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The DataTable contains... 376 columns

At least, I think that's what Excel's NL column converts to. I just looked up the column count now and had no idea there were so many. Our software vendor hasn't realized the value of dynamic sql statements for this process, so every software "upgrade" just keeps adding more columns rather than only selecting the ones needed. I cannot alter the SQL statement that generates the data
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Here's the code. Forgive the mess, I wrote it back when I didn't know what I was doing and when I still was working in VB

Function ReadDataTableForCSV(dt as DataTable)
Dim sb = New StringBuilder()
Dim dataTypes As New Dictionary(Of String, Integer)

[code]....

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VS 2010 Filter Data With DataTable And DataView?

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I'm loading a DataGridView from a DataView which collects data from a DataTable. I use the DataView to filter, this is the

Dim dv As New DataView
dv = DataSet4.Tables("TABLA1").DefaultView
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[code].....

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[Code]...

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[Code]...

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da.SelectCommand = New SqlCommand(sqlStatement, tempDB.Connection)
da.MissingSchemaAction = MissingSchemaAction.AddWithKey
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da.Fill(dt)

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da.SelectCommand = New SqlCommand(sqlStatement, tempDB.Connection)
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Public Function GetDataSet() As DataSet
Dim ds As DataSet
ds = New DataSet

[code].....

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[Code]...

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This is a sample code

Dim dt As New DataTable
dt.Columns.Add("ID")
dt.Columns.Add("Time")
[CODE]...

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Imports System.Data.SqlClient
Imports System
Imports System.IO[code].....

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the code is

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[Code]......

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Me.DtShifts.Tables("NonAllocated").Clear()
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[Code]...

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[Code]...

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Try
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[Code]....

My understanding is that if I make changes in the datagridview it is reflected in the datatable.

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