Did you read Documentation for flexgrid
?
there is so many samples of various works with flexgrid
here is :
Edited :
use HitTest
to find if a cell is double clicked
void c1FlexGrid1_MouseDoubleClick(object sender, MouseButtonEventArgs e)
{
var ht = c1FlexGrid1.HitTest();
if (ht.Row!=-1)
{
MessageBox.Show("Click on row no--" + ht.Row);
//do something
}
}