• Status: Solved
  • Priority: Medium
  • Security: Public
  • Views: 348
  • Last Modified:

Delete node in treeview and its associated row in a database table

Hi,

I have made this code and the purpose of it is to delete a node in the treeview
and its associated row from the table. The last part does not work.

        private void tbDelNode_Click(object sender, EventArgs e)
        {
            myDataSet.Tables["Customers"].Rows[0].Delete();  <===
            myDataAdapter.Update(myDataSet, "Tree");
        }


Only the line marked with an arrow is not right. I get the message:
Object reference not set to an instance of an object.

Who can help me that when i selec a certain node of a treeview
the treeviewnode and its associated table row will be deleted.

Peter
0
peterkiers
Asked:
peterkiers
  • 3
1 Solution
 
jagssiduralaCommented:
There are 2 reasons to get the error mentioned.
myDataSet.Tables["Customers"].Rows[0].Delete();

1) May be myDataset is null
2) There is no table with the table name called "Customers"(Check your spelling) in myDataSet
0
 
peterkiersAuthor Commented:
oke:

      private void tbDelNode_Click(object sender, EventArgs e)
        {
            myDataSet.Tables["Tree"].Rows[0].Delete();  <===
            myDataAdapter.Update(myDataSet, "Tree");
        }
And now...
0
 
peterkiersAuthor Commented:
I have this but it deletes always the first row of the table:

        {

              myDataSet.Tables["Tree"].Rows[0].Delete();  <==================
            myDataAdapter.Update(myDataSet, "Tree");
            tvNotes.SelectedNode.Remove();
        }

Greetings, Peter Kiers
0
 
peterkiersAuthor Commented:
Thanks for the info
0

Featured Post

Never miss a deadline with monday.com

The revolutionary project management tool is here!   Plan visually with a single glance and make sure your projects get done.

  • 3
Tackle projects and never again get stuck behind a technical roadblock.
Join Now