C#

class Form1 : Form
{
   public Form1()
   {
      BackgroundWorker worker = new BackgroundWorker();
      worker.DoWork += (sender, e) => 
          {
              // This will run on the background thread.
              e.Result = cashFlow.GetAttrForCashflow(cashFlow.CashflowID);
          };
      worker.RunWorkerCompleted += (sender, e) => 
          {
              // This will run on the UI thread.
              var dataTable = (DataTable)e.Result;
              UIUtils.dgLoad(dataTable, dataTable.DefaultView, "");
          };
      worker.RunWorkerAsync();
   }
}

private void LoadGrid()
{
   try
   {
	if (this.InvokeRequired) // returns true since you are on a new thread
	{
            this.BeginInvoke(new LoadGridDelegate(LoadGrid), null); // delegates to main thread and <code>LoadGrid</code> will be called again. 
Now <code>InvokeRequired</code> will be false and else conditions executes.
	}
	else
	{
            // This part will be executed on main thread. and it hangs until this operation is finished
            DataTable dtAttr = cashFlow.GetAttrForCashflow(cashFlow.CashflowID);
	    UIUtils.dgLoad(dgAttr, dtAttr.DefaultView, "");
	}
   }
   catch (Exception)
   { throw; }  // if you are just throwing, you don't need to handle it
}

private void LoadGrid()
{
   // data loading is happening in new thread
   DataTable dtAttr = cashFlow.GetAttrForCashflow(cashFlow.CashflowID);
   this.BeginInvoke((MethodInvoker)delegate
   {
       // this will be on main thread
       UIUtils.dgLoad(dgAttr, dtAttr.DefaultView, "");
   });
}

Mycroft Holmes wrote:

Now to do some research on MethodInvoker

N a v a n e e t h wrote:

method which will have no parameters.

private void LoadGrid(DataTable dtAttr)	{
	if (this.InvokeRequired) {
		// execute on current thread
		dtAttr = cashFlow.GetAttrForCashflow(cashFlow.CashflowID);
		this.BeginInvoke(new LoadGridDelegate(LoadGrid), dtAttr );
	} else {
		// execute on GUI thread
		UIUtils.dgLoad(dtAttr, dtAttr.DefaultView, "");
	}
}

if(DGV.SelectedItems.count == 0)<br />
{return ;}