dataset

[juli jul]

Hello,I am trying to retrieve a column from a dataset which will be in
array as a collection of strings.
I am doing something like that:

ds = new DataSet();
Adapter1.Fill(ds);
MessageBox.Show(ds.Tables["n"].Columns["p"].ToString());

but it's not working (it gives the :Object reference not set to an
instance of an object.)
why? how can I do it?
Thanks a lot!

 

[Cor Ligthert]

You mean something as this one?

MessageBox.Show(ds.Tables["n"].Columns["p"].ColumnName.ToString());

Or something else, this is a little bit strange sentence because this shoud
give "p".

Cor

 

[juli jul]

Hello,
No,I need the data inside the column ,how do I do that?
Thanks

 

[Reshma Prabhu]

Hi,

Check the Tables property of database. Check whether the table named "n" is
present there.
If that table is present check whether column named "p" is present Columns
property of that table.

It gives "Object reference not set to an instance of an object." as it is
not getting one of the two things,

Hope this helps.

Regards,
Reshma

 

[Cor Ligthert]

Juli,

The columns describes the items

The items self you get with
MessageBox.Show(ds.Tables["n"].Rows[x]["p"].ToString());

where "Item: is default it is official
MessageBox.Show(ds.Tables["n"].Rows[x].Item["p"].ToString());

I hope his helps

Cor

 

[juli jul]

Thanks it is but I have another question refering to it:
I am doing the :

this.comboBox1.DataBindings.Add("SelectedValue",ds.Tables[0].Rows["na
me"],"sysobjects.name");

and get this error:
An unhandled exception of type 'System.ArgumentException' occurred in
system.windows.forms.dll

Additional information: This would cause two bindings in the collection
to bind to the same property.

Why and how to solve this?
Thanks!

 

[Cor Ligthert]

Juli,

Because you have to bind it to the table not to the rows, that is affected
by the currencymanager a sample

this.textBox1.DataBindings.Add("Text",ds.Tables[0],"name");

However what you do will never go. For that is not the databindings

You probably want to set the
combobox1.SelectedIndex = Integer;

Cor

 

[juli jul]

Hello,
I have a dataset ,it contains a table with one column named "name" - I
want to add all the rows under this column(each one of the a string) to
a combobox as a source.
How can I do that?
Thanks a lot!

 

[Cor Ligthert]

Juli

combobox1.DataSource = ds.tables[0];
combobox1.DisplayMember = "name"

I hope this helps,

Cor

 

[juli jul]

Thank you-it helped.I don't know why I was insisting on binding,this one
works fine.