
[ToolboxItem(true)]
public class PictureBoxURL : PictureBox
{
private string _url = "";
public string ImageUrl
{
get
{
return _url;
}
set
{
_url = value;
if (String.IsNullOrEmpty(_url)) return;
GetImageByWebRequest(this, _url);
}
} public Image ImageLoading { get; set; } /// <summary>
/// 推荐使用ByWebRequest
/// </summary>
/// <param name="edit"></param>
/// <param name="url"></param>
private void GetImageByWebClient(PictureBoxURL edit, string url)
{
WebClientImage tt = new WebClientImage(edit, url);
Thread thread = new Thread(new ThreadStart(tt.Do));
thread.Start(); }
private void GetImageByWebRequest(PictureBoxURL edit, string url)
{
WebRequestImage tt = new WebRequestImage(edit, url);
Thread thread = new Thread(new ThreadStart(tt.Do));
thread.Start();
} public class WebClientImage
{
private PictureBoxURL edit;
private string url; public WebClientImage(PictureBoxURL a, string b)
{
edit = a;
url = b;
} public void Do()
{
try
{
edit.BeginInvoke(new Action(() =>
{
edit.Image = edit.ImageLoading;
})); using (var client = new System.Net.WebClient())
{
using (var strream = client.OpenRead(url))
{ Image Image = new Bitmap(strream);
edit.BeginInvoke(new Action(() =>
{
edit.Image = Image;
}));
}
}
}
catch
{
edit.BeginInvoke(new Action(() =>
{
edit.Image = null;
}));
}
}
}
private class WebRequestImage
{
private PictureBoxURL edit;
private string url; public WebRequestImage(PictureBoxURL a, string b)
{
edit = a;
url = b;
}
public void Do()
{
try
{
if (edit.IsHandleCreated)
{
edit.BeginInvoke(new Action(() =>
{
edit.Image = edit.ImageLoading;
}));
}
else
edit.Image = edit.ImageLoading; var request = (HttpWebRequest)WebRequest.Create(url); using (var response = (HttpWebResponse)request.GetResponse())
{
if (response.StatusCode == HttpStatusCode.OK)
{
using (var stream = response.GetResponseStream())
{
Image Image = new Bitmap(stream);// Bitmap.FromStream(stream);
edit.BeginInvoke(new Action(() =>
{
edit.Image = Image;
})); }
}
}
}
catch (Exception ex)
{
try
{
edit.BeginInvoke(new Action(() =>
{
edit.Image = null;
}));
}
catch { }
}
}
}
}