C#

<br />
private void purchase_Click    ( object sender, System.EventArgs e )<br />
{<br />
	lock ( f )<br />
	{<br />
		try<br />
		{<br />
			fs = f.OpenWrite( ) ;<br />
			byte b = byte.Parse ( quantity.Text ) ;<br />
			total = ( byte ) ( total - b ) ; <br />
			fs.WriteByte ( total ) ;<br />
			MessageBox.Show ( "Transaction Complete" + "\n" + "Item    <br />
			remaining: " + total ) ;<br />
			fs.Close( ) ;<br />
		}<br />
		catch<br />
		{<br />
			MessageBox.Show ( "Cannot Open file" ) ;<br />
		}<br />
   }<br />
}<br />

// remove head
if (myList.Count > 0)
  myList.RemoveAt(0); 

lock(myList.SyncRoot)
{
  if (myList.Count > 0)
    myList.RemoveAt(0); 
}

kumar.bs wrote:

if we synchronize the whole method, how other thread can make calls between Count and RemoveAt?

kumar.bs wrote:

lock(mylist.syncRoot) can't we specify lock(mylist)?