C#

<br />
parms[0].Value = null;<br />

<br />
if( _categoryID == -1 )<br />
{<br />
   parms[0].Value = null;<br />
}<br />
else<br />
{<br />
   parms[0].Value = _categoryID;<br />
}<br />

		private void button1_Click(object sender, System.EventArgs e)<br />
		{<br />
			Bitmap bmp = new Bitmap(16, 16);<br />
			Graphics g = Graphics.FromImage(bmp);<br />
			<br />
			Font f = new Font("Arial", 5);<br />
			LinearGradientBrush b = new LinearGradientBrush(ClientRectangle, Color.Red, Color.Red, LinearGradientMode.Horizontal);<br />
			g.DrawString("ABC", f, b, 1, 1);<br />
			pictureBox1.Image = bmp;<br />
<br />
			bmp.Save("d:\\test.ico", ImageFormat.Icon);<br />
			Icon = new Icon("d:\\test.ico");<br />
		}

public void CallingMethod()<br />
{<br />
    // Calling Process() method numerous times, aquiring numerous IAsyncResults<br />
<br />
    // Iterating over all IAyncResults aquired above and waiting for each WaitHandle.<br />
<br />
    // Ups, sometimes there are no error messages in the IAyncResult.AsyncState<br />
}<br />
<br />
public IAsyncResult Process()<br />
{<br />
    IAsyncResult asyncResult = myWebRequest.BeginGetResponse(RespCallback, myRequestState);<br />
    return asyncResult;<br />
}<br />
<br />
private void RespCallback(IAsyncResult asyncResult)<br />
{<br />
    try<br />
    {<br />
        resp = req.EndGetResponse(asyncResult);<br />
    }<br />
    catch (Exception ex)<br />
    {<br />
        string errorMessage = string.Format("host unreachable...");<br />
        // Before adding this error message the WebRequests WaitHandle is released!<br />
        ((MyRequestState)asyncResult.AsyncState).AddStatusMessage(errorMessage);<br />
    }<br />
}