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Importing CSV into DataTable datatype problem VB 2010

Hi

Im importing a CSV file into a datatable, it all goes well, except that I have a few columns that have rows which contain eaither a number or "????" . Unfortunatly the code that I have converst this column of data into double and my "????" are then turned into zero.

I would like to change the data columns datatype but I havent been able to do so even though I change the type prior to filling the table (see code). how do force the columns to be read as text ?

Michal

Dim sConnectionString As String = "Provider=Microsoft.Jet.OLEDB.4.0;Data Source=" & Path.GetDirectoryName(CSVName) & "\;Extended Properties=""text;HDR=YES;FMT=Delimited"""
            Dim objConn As New System.Data.OleDb.OleDbConnection(sConnectionString)
            Dim da As OleDb.OleDbDataAdapter



            'Open Data Adapter to Read from Text file
            Dim str As String = "SELECT * FROM [" & Path.GetFileName(CSVName) & "]"
            da = New System.Data.OleDb.OleDbDataAdapter(str, objConn)
            'Fill dataset using dataadapter
            da.FillSchema(SystemTable, SchemaType.Mapped)

            For Each column As DataColumn In SystemTable.Columns
                If column.ColumnName = "WINDIV" Then column.DataType = System.Type.GetType("System.String")
                If column.ColumnName = "PLCDIV" Then column.DataType = System.Type.GetType("System.String")
                If column.ColumnName = "SPDIV" Then column.DataType = System.Type.GetType("System.String")

            Next

            da.Fill(SystemTable)
            objConn.Close()

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puppydogbuddy

Just an educated guess:
change this portion of your code: column.DataType = System.Type.GetType("System.String")

to this: column.DataType = System.Type.GetType("String")

MichMat

ASKER

throws up an error Im sorry to say that the column data type is not recognised

puppydogbuddy

see: http://www.functionx.com/vbnet/oledb/Lesson02.htm
There are two primary pieces of information you must specify for each column: its name and its type. Therefore, the syntax of creating a column is:

ColumnName DataType Options

Change:
column.DataType = System.Type.GetType("System.String")

To this:
columnName.DataType = System.Type.GetType("System.String")
or
columnName.DataType = System.Type.GetType("System.Char")
or
columnName.DataType = System.Type.GetType("System.SqlString")

puppydogbuddy

forgot to tell you to replace columnName above with your actual column name.

MichMat

ASKER

Hi ,

Thanks for helping , so far all I can gathre that Microsoft will relentlesly 'help' me !

System.ArgumentException: Invalid cast from 'Double' to 'Char'.Couldn't store <4> in WINDIV Column.

the SQLSTring get the same datatype error as mentioned in previous post.

It seam a crazy behaviour, I can load the table by using streemreader and get what I need but this process takes a minute and a bit to load the table , splitting each line as opposed to less then 10 seconds with the way that I have here.

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puppydogbuddy

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MichMat

ASKER

Hi ,

Thanks , that is a veru usefull link. I didnt have any luck with varchar, I guess that JET is very limited in what it will accept. I have been able to change the tables columns as we seen , but JET still converts the data to what ever it thinks it should be and then tries to fit a square peg into a round hole. ie Double into a char or even string.

My only option may be to force the columns to be cast when they are read ...... that would mean writing out a select statment with 162 columns !! But I havent figured out how to cast , I have used it in SQL but Jet just refuses to accept it , but I havent done much reaserch in that area yet