Re: Record Lookup

MikeS,

The problem is that a novice can ask more difficult questions than somebody who knows what he wants.

You have at least two options:
find what you want in direct in the database
find what you want in a datatable.

For both you got an answer. The first is very well with very hug databases. The latter is better if it is about smal databases.

Cor

"MikeS" <MikeS@xxxxxxxxxxxxxxxxxxxxxxxxx> schreef in bericht news:6B01D10B-5A7F-41ED-80E9-8D49B11763C5@xxxxxxxxxxxxxxxx
Patrice, thank you for your comments and effort. Unfortunately, that doesn't
tell me what I need to know. As I originally mentioned, I am a novice and
any help would have to be in the form of very precise syntax or at least a
very good example. I also mentioned that I tried setting changing the
primary key in the table to the field that I wanted to use for the search
criteria and that didn't work.

Any additional information you could add would be greatly appreciated.

Thanks,

Mike

"Patrice" wrote:

From http://msdn2.microsoft.com/en-us/library/ydd48eyk.aspx (Find
documentation) :

[To use the Find method, the DataTable object to which the DataRowCollection
object belongs must have at least one column designated as a primary key
column. See the PrimaryKey property for more information about how to create
a primary key column.]

So Find can only search using the primary key...

Depending on what you are trying to do you could use the DataTable.Select
method or DataTable.DefaultView.RowFilter property to select rows using a
more general criteria.

A a side note (and I know this is not your code) IMO it would better to
check explicitely if the criteria returns nothing. The code doesn't work if
a row is not found. It raises an error and then display a message saying
that the row is not found. Actually it will display the message regardless
of the real reason for which the code fails (for example you could test if
the found row is nothing so that an error is raised only if you have a real
error)...

---
Patrice

"MikeS" <MikeS@xxxxxxxxxxxxxxxxxxxxxxxxx> a écrit dans le message de news:
EF0501C3-CC9B-4A5E-A4F3-DBC53163777E@xxxxxxxxxxxxxxxx
>
> The Access file name is "ItemMaster.dbf"
> The table name is "Itemlist"
> The field names are "ID (primary), ITNBR, ITDSC, UCDEF"
>
> This is the code that populates the combobox:
>
> cboItemNum.DataSource = ItemMasterDataSet1.Tables("ItemList")
> cboItemNum.DisplayMember = "ID"
>
> The following is the code snippet I found to search the table:
>
> Dim strItemNum As String
> Dim drSelectedRecord As DataRow
> strItemNum = cboItemNum.Text
>
> drSelectedRecord =
> ItemMasterDataSet1.ItemList.Rows.Find(strItemNum)
>
> Try
> lblItemDesc2.Text = drSelectedRecord(1).ToString & _
> " - " & drSelectedRecord(2).ToString
>
> Catch ex As Exception
> MsgBox("Record " & strItemNum & " was not found.")
>
> End Try
>
> The problem is I can only search by "ID" and I want to search by > "ITNBR".
> I
> have
> tried changing the primary field and "DisplayMember" to "ITNBR". This
> will
> change the field in my combo box but I get an error when I do the > lookup.
>
> Let me know if you need any additional information.
>
> Thanks in advance.
>
> Mike
>
>
> "rowe_newsgroups" wrote:
>
>> On Sep 11, 9:18 am, MikeS <Mi...@xxxxxxxxxxxxxxxxxxxxxxxxx> wrote:
>> > I have searched Google with every possible combination of key words >> > I
>> > can
>> > imagine and have not been able to find an answer to what I think is >> > a
>> > very
>> > simple question and probably has a very simple solution.
>> >
>> > Keep in mind.....I am a NOVICE programmer, so you will have to spell >> > it
>> > out
>> > for me.
>> >
>> > I am trying to write a very simple program in VB.Net 2005. that will
>> > search
>> > a single Access database table and return the value of one field >> > based
>> > on
>> > criteria that I provide for any other field I choose. The only way >> > I
>> > have
>> > had any success is if I search by the primary key field, which does >> > not
>> > give
>> > me the versatility that I need.
>> >
>> > Can anyone point me to some sample code that will help me accomplish
>> > this?
>> >
>> > Thanks in advance.
>> >
>> > Mike
>>
>> You should connect with the OleDb database providers and then do the
>> search with a simple Sql query.
>>
>> If you post a bit of the target table's schema (column names mainly)
>> and tell me which fields you need to search I'll be more than happy to
>> write up some simple code for you.
>>
>> Thanks,
>>
>> Seth Rowe
>>
>>




.

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