Passing DataContext to Button Event Handler

[=?Utf-8?B?UGFvbG8=?=]

How do I pass a DataContext to a button_click event handler. I have the
following:

public partial class frmMain : Form
{
public frmMain()
{
InitializeCompo nent();

string cnStr =
@"Data Source=.\SQLEXP RESS;AttachDbFi lename=L:\Works pace\SQL
Databases\Train ing.mdf;"
+ "Integrated Security=True;C onnect Timeout=30;User
Instance=True";

DBDataContext db = new DBDataContext(c nStr); // typed DataContext
}

private void btnList_Click(o bject sender, EventArgs e)
{
var act_types =
from a in db.Activities // error: name 'db' does not exist
in
// the current
context
from t in db.Types // ditto
where a.Activity_Type == t.Type_Id

orderby a.Activity_Date
select new
{
a.Activity_Date ,
t.Type_Desc,
a.Activity_Dist ance,
a.Activity_Dura tion,
a.Activity_Rout e
};

dgvList.DataSou rce = act_types; // show query results in
DataGridView

}

Thanks

[Stefan Hoffmann]

hi Paolo,

Paolo wrote:

How do I pass a DataContext to a button_click event handler.

Use a global variable:

public partial class frmMain : Form
{
DBDataContext _DataContext = null;

public frmMain()
{
InitializeCompo nent();
string cnStr = @"Data Source=.\...";>
_DataContext = new DBDataContext(c nStr); // typed DataContext
}

private void btnList_Click(o bject sender, EventArgs e)
{
var act_types = from a in _DataContext.Ac tivities ...
}
}
mfG
--stefan <--

[=?Utf-8?B?UGFvbG8=?=]

Stefan: yes, visibility. This hit me while lying in bed this morning. Thx.

"Stefan Hoffmann" wrote:

hi Paolo,

Paolo wrote:

How do I pass a DataContext to a button_click event handler.

Use a global variable:

public partial class frmMain : Form
{
DBDataContext _DataContext = null;

public frmMain()
{
InitializeCompo nent();
string cnStr = @"Data Source=.\...";>
_DataContext = new DBDataContext(c nStr); // typed DataContext
}

private void btnList_Click(o bject sender, EventArgs e)
{
var act_types = from a in _DataContext.Ac tivities ...
}
}
mfG
--stefan <--