passing a different sql string to DataAdapter each time i click a button

eksypnos123

private void button1_Click(object sender, System.EventArgs e) { ds.Tables.Clear(); da.SelectCommand=new SqlCommand(textBox1.Text,sqlConnection1); da.Fill(ds,"myTable"); dataGrid1.SetDataBinding(ds,"myTable"); } I have a form with a textBox1, a dataGrid1 and a button1. In the textBox1 I write some sql code and I want to see the output in the grid. ds is a dataset and da is a dataAdapter that were instantiated once in the constructor without any parameters. (ds=new DataSet(), da=New DataAdapter()). My problems is that this code seems to execute only the first time I click the button. After the first time the datagrid doesn't change although i put different sql code in the textBox. Can somebody tell me why is this happening?

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p.jones22y ago
I will suspect that first time you fill the DataTable MyTable the DataAdapter configures the DataTable's schema, and if your subsequent SQL returns different schema then MyTable just doesn't get changed. So you need to look at that. You may need to drop the DataTable MyTable, each time, or FillSchema before Fill. Just a guess since I have never tried to get one DataTable to hold results of consecutive arbitrary SQL SELECTS.
eksypnos12322y ago
I think I had tried this and works, but I don't want to instantiate a new DataAdapter and DataSet each time I click the button. So isn't possible to change the selectCommand of the SqlDataAdapter after it's assigned or it has something to do with the grid?
Carlos Sanchez22y ago
try this: private void button1_Click(object sender, System.EventArgs e) { ds = new DataSet(); ds = new SqlDataAdapter(textBox1.Text, sqlConnection1); da.Fill(ds,"myTable"); dataGrid1.SetDataBinding(ds,"myTable"); } Regards.