can't access object in finally-block [solved] - C# Discussion Boards

Re: can't access object in finally-block

16-Jan-07 4:17

In the finally block, you need to check that sr is not null before calling the Close method. This would become:

finally
{
  if (sr != null)
    sr.Close();
  return retval;
}

the last thing I want to see is some pasty-faced geek with skin so pale that it's almost translucent trying to bump parts with a partner - John Simmons / outlaw programmer

Deja View - the feeling that you've seen this post before.

J4amieC16-Jan-07 5:09

J4amieC

16-Jan-07 5:09

You probably have to initialise sr before the try - plus use the method Pete suggested of checking for null.

// make sure this is pre-initialised<br />
StreamReader sr = null;<br />
<br />
try<br />
{<br />
  sr = new StreamReader(new FileStream(filename, FileMode.Open, FileAccess.Write));<br />
}<br />
catch(Exception ex)<br />
{<br />
  // do something with the exception<br />
}<br />
finally<br />
{<br />
  if(sr != null)<br />
    sr.Close();<br />
}

---

How to get answers to your questions[^]

Re: can't access object in finally-block

Drum D.16-Jan-07 7:33

Drum D.

16-Jan-07 7:33

Actually initializing it with null did the trick. I'va done too much PHP Wink | ;)

Thanks

Scope_identity() doesn't work

cruscotto16-Jan-07 3:45

cruscotto

16-Jan-07 3:45

Hi!

I have a problem about Scope_identity function();

I've created a dataset with two table, parent and child.
I've configurated both tables with the wizard; in that way for each insert and update of my records I obtain the correct ID.

The problem is that the queries of the child table doesn't return the updated ID, after my inserting or updating in the SQL Server.

I've looked into into the DatasetDesigner.cs, and I've read the queries. Both Update and Insert query have the end-select.

What is the reason of the problem?
What is my error?

Thank you for answers.

Re: Scope_identity() doesn't work

Dave Kreskowiak16-Jan-07 5:51

Dave Kreskowiak

16-Jan-07 5:51

Yes, it does work, but only if used properly. What does you C# code looks like that's expecting this to work? What does the SQL look like?

Dave Kreskowiak
Microsoft MVP - Visual Basic

Re: Scope_identity() doesn't work

cruscotto16-Jan-07 6:08

cruscotto

16-Jan-07 6:08

this is the query:

this._adapter.InsertCommand.CommandText = @"INSERT INTO [P_OrdiniRighe] ([IdOrdine], [CodiceArticoloInterno], [CodiceArticoloEsterno], [CodiceFinitura], [CodiceVariante], [Quantita], [DataConsegna], [QuantitaConsegnata], [UM], [Prezzo], [Note], [QuantitaImpegnata]) VALUES (@IdOrdine, @CodiceArticoloInterno, @CodiceArticoloEsterno, @CodiceFinitura, @CodiceVariante, @Quantita, @DataConsegna, @QuantitaConsegnata, @UM, @Prezzo, @Note, @QuantitaImpegnata);<br />
SELECT IdRigaOrdine, IdOrdine, CodiceArticoloInterno, CodiceArticoloEsterno, CodiceFinitura, CodiceVariante, Quantita, DataConsegna, QuantitaConsegnata, UM, Prezzo, Note, QuantitaImpegnata FROM P_OrdiniRighe WHERE (IdRigaOrdine = SCOPE_IDENTITY())";

this._adapter.UpdateCommand.CommandText = @"UPDATE [P_OrdiniRighe] SET [IdOrdine] = @IdOrdine, [CodiceArticoloInterno] = @CodiceArticoloInterno, [CodiceArticoloEsterno] = @CodiceArticoloEsterno, [CodiceFinitura] = @CodiceFinitura, [CodiceVariante] = @CodiceVariante, [Quantita] = @Quantita, [DataConsegna] = @DataConsegna, [QuantitaConsegnata] = @QuantitaConsegnata, [UM] = @UM, [Prezzo] = @Prezzo, [Note] = @Note, [QuantitaImpegnata] = @QuantitaImpegnata WHERE (([IdRigaOrdine] = @Original_IdRigaOrdine) AND ([IdOrdine] = @Original_IdOrdine) AND ([CodiceArticoloInterno] = @Original_CodiceArticoloInterno) AND ([CodiceArticoloEsterno] = @Original_CodiceArticoloEsterno) AND ([CodiceFinitura] = @Original_CodiceFinitura) AND ([CodiceVariante] = @Original_CodiceVariante) AND ([Quantita] = @Original_Quantita) AND ([DataConsegna] = @Original_DataConsegna) AND ([QuantitaConsegnata] = @Original_QuantitaConsegnata) AND ([UM] = @Original_UM) AND ([Prezzo] = @Original_Prezzo) AND ([Note] = @Original_Note) AND ([QuantitaImpegnata] = @Original_QuantitaImpegnata));<br />
SELECT IdRigaOrdine, IdOrdine, CodiceArticoloInterno, CodiceArticoloEsterno, CodiceFinitura, CodiceVariante, Quantita, DataConsegna, QuantitaConsegnata, UM, Prezzo, Note, QuantitaImpegnata FROM P_OrdiniRighe WHERE (IdRigaOrdine = @IdRigaOrdine)";

They are generated automatically...

This is the function for updating e inserting

public static void UpdateParentChildObject(<br />
            DataTable oParentTable, DbDataAdapter oParentTableAdapter,<br />
            DataTable oChildTable, DbDataAdapter oChildTableAdapter)<br />
        {<br />
            // tabelle temporanee per le righe modificate delle tabelle child<br />
            DataTable tblChildDeleted = null;<br />
            DataTable tblChildAdded = null;<br />
            DataTable tblChildModified = null;<br />
            <br />
            try<br />
            {<br />
                // salvataggio in sequenza:<br />
                // 1) child eliminate<br />
                // 2) master<br />
                // 3) child aggiunte<br />
                // 4) child modificate<br />
                // ricavo le righe child eliminate<br />
                tblChildDeleted = oChildTable.GetChanges(DataRowState.Deleted);<br />
                if (tblChildDeleted != null)<br />
                    oChildTableAdapter.Update(tblChildDeleted);<br />
<br />
                oParentTableAdapter.Update(oParentTable);<br />
                oParentTable.AcceptChanges();<br />
<br />
                // ricavo le righe child aggiunte<br />
                tblChildAdded = oChildTable.GetChanges(DataRowState.Added);<br />
                if (tblChildAdded != null)<br />
                    oChildTableAdapter.Update(tblChildAdded);<br />
<br />
                // ricavo le righe child modificate<br />
                tblChildModified = oChildTable.GetChanges(DataRowState.Modified);<br />
                if (tblChildModified != null)<br />
                    oChildTableAdapter.Update(tblChildModified);<br />
<br />
                // modifche accettate<br />
                oChildTable.AcceptChanges();<br />
<br />
            }<br />
            finally<br />
            {<br />
                if (tblChildDeleted != null)<br />
                    tblChildDeleted.Dispose();<br />
<br />
                if (tblChildAdded != null)<br />
                    tblChildAdded.Dispose();<br />
<br />
                if (tblChildModified != null)<br />
                    tblChildModified.Dispose();<br />
            }<br />
        }

Tell me if you need more information

Re: Scope_identity() doesn't work

Dave Kreskowiak16-Jan-07 8:06

Dave Kreskowiak

16-Jan-07 8:06

I fail to see where you're returning SCOPE_IDENTITY out of the database.

SCOPE_IDENTITY[^] will return the identity column of the last record INSERTed into a table. You're not inserting anything into the table with this code, so of course it's not going to return anything. On top of that, your SQL code isn't event returning the value of SCOPE_IDENTITY. You may want to read up on it so you get a better understanding of what it does.

Dave Kreskowiak
Microsoft MVP - Visual Basic

help!! replace string

vanudu16-Jan-07 3:42

16-Jan-07 3:42

i need to write a program that gets a string from the user,a replacement string and finally the new string.
ex aaabbb
aaa
zzz
output zzzbbb
i need to use a function replaceStr. can anyone help me?
thanks

Pete O'Hanlon16-Jan-07 3:47

16-Jan-07 3:47

You need to look at the string.Replace method.

vanudu16-Jan-07 3:48

16-Jan-07 3:48

where can i find it?

Pete O'Hanlon16-Jan-07 3:56

16-Jan-07 3:56

The answers below have it.

vanudu16-Jan-07 4:02

16-Jan-07 4:02

rhank you for youre kind help. i'm really struggling with this language..anyway, below was posted a specific ex, i dont have the strings in advance. i need to allocate memory for thr new string.

Pete O'Hanlon16-Jan-07 4:15

16-Jan-07 4:15

This is the C# forum. You don't need to allocate memory for this because this is taken care of automatically. Your routine would probably be along the lines of:

public string MyReplace(string original, string valueToReplace,  string replace)
{
  if (original.IsNullOrEmpty || replace.IsNullOrEmpty ||valueToReplace.IsNullOrEmpty)
    throw new Exception("One of the arguments is empty or null");
  return orignal.Replace(valueToReplace, replace);
}

Seishin#16-Jan-07 3:49

Seishin#

16-Jan-07 3:49

<br />
string str = "aaabbb";<br />
string toReplace = "aaa";<br />
string replacement = "zzz";<br />
<br />
str = str.Replace(toReplace, replacement);

life is study!!!

vanudu16-Jan-07 3:58

16-Jan-07 3:58

thank you for you're kind help. the thing is tose are specific ex, i dont know in advance what will be my toreplace string and the replacement. also, i need to alocate memory for the new string

Dave Kreskowiak16-Jan-07 5:53

Dave Kreskowiak

16-Jan-07 5:53

Do you want us to write your entire project for you?

Dave Kreskowiak
Microsoft MVP - Visual Basic