WPF下载和取消下载功能并显示进度条
记录一个小案例：下载和取消下载（还可以用事件与委托的形式实现），但是我没有用，我这个比较简单
话不多说直接上案例：
前台页面"XRKAddin.Versions.UpdateVersion" xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation" xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml" xmlns:mc="http://schemas.openxmlformats.org/markup-compatibility/2006" xmlns:d="http://schemas.microsoft.com/expression/blend/2008" xmlns:local="clr-namespace:XRKAddin.Versions" mc:Ignorable="d" xmlns:hc="https://handyorg.github.io/handycontrol" Height="500" Width="400" WindowStartupLocation="CenterScreen" WindowStyle="None" AllowsTransparency="True" BorderThickness="24" xmlns:wpfanimated="http://wpfanimatedgif.codeplex.com" Title="关于" ShowInTaskbar="False" ResizeMode = "NoResize" Loaded="Window_Loaded"> "20" Color="#FF858484" Direction="300" ShadowDepth="0" Opacity="0.5"/> "#0D6FB8" BorderThickness="1" > "../Resources/login/cloud.png" Opacity=".1" RenderOptions.CacheInvalidationThresholdMinimum="0.5" RenderOptions.CacheInvalidationThresholdMaximum="2.0" RenderOptions.CachingHint="Cache" Viewport="0,0,157,157" ViewportUnits="Absolute" Stretch="Uniform" TileMode="Tile"/> "50"/> "400"/> "0" Orientation="Horizontal" Background="#D8D8D8" Height="50" hc:WindowAttach.IsDragElement="True"> "../Resources/icon_about.png" Width="18" Height="18" Margin="18,0"/> "关于" Height="18"/> "1"> "60"/> "40"/> "40"/> "105"/> "*"/> "0" Text="Call-Link" Height="20" FontSize="18" FontWeight="Black" HorizontalAlignment="Center"/> "1" Name="version" Text="当前版本1.0.1" Height="20" HorizontalAlignment="Center" Foreground="#BDBDBD"/> "2" Orientation="Horizontal" HorizontalAlignment="Center" Name="panel1"> "image1" wpfanimated:ImageBehavior.AnimatedSource="../Resources/gengxin1.gif" wpfanimated:ImageBehavior.RepeatBehavior="0x" wpfanimated:ImageBehavior.AnimateInDesignMode="True" wpfanimated:ImageBehavior.AutoStart="True" Height="18" Width="18" Margin="10"/> "image" Source="../Resources/gengxin.png" Width="18" Height="18" Margin="10" Visibility="Collapsed"/> "inspect" Text="正在检查更新" Height="20" HorizontalAlignment="Center" /> "3"> "350"/> "Horizontal"> "4"> "20,20,20,0"> "progressbar" Style="{DynamicResource ProgressBarSuccess}" Width="250" Visibility="Collapsed"> "../Resources/bg.png"/> "70"> "../Resources/logo.png" Width="102" Height="19"/> "20" HorizontalAlignment="Center" Margin="0,100"> "link" NavigateUri="http://www.sunmooc.cn/" ToolTip="欢迎访问，向日葵教育" Click="Hyperlink_Click">www.sunmooc.cn
public bool DownloadFile(string URL, string fileName, ProgressBar progressBar1) { System.IO.Stream stream1 = null; System.IO.Stream stream2 = null; try { System.Net.HttpWebRequest httpWebRequest1 = (System.Net.HttpWebRequest)System.Net.HttpWebRequest.Create(URL); System.Net.HttpWebResponse httpWebResponse1 = (System.Net.HttpWebResponse)httpWebRequest1.GetResponse(); long totalLength = httpWebResponse1.ContentLength; if (progressBar1 != null) { progressBar1.Maximum = (int)totalLength; } stream1 = httpWebResponse1.GetResponseStream(); stream2 = new System.IO.FileStream(fileName, System.IO.FileMode.Create); long currentLength = 0; byte[] by = new byte[1024]; int osize = stream1.Read(by, 0, (int)by.Length); while (osize > 0) { if (isDownload) { throw new Exception("手动停止下载！"); } //WpfApplication.DispatcherHelper.DoEvents(); System.Windows.Forms.Application.DoEvents(); currentLength = osize + currentLength; stream2.Write(by, 0, osize); if (progressBar1 != null) { progressBar1.Dispatcher.BeginInvoke((ThreadStart)delegate { progressBar1.Value = (int)currentLength; }); //progressBar1.Value = (int)currentLength; //label1.Text = String.Format("{0} / {1}", BytesToString(currentLength), BytesToString(totalLength)); } osize = stream1.Read(by, 0, (int)by.Length); } stream2.Close(); stream1.Close(); return (currentLength == totalLength); } catch { isDownload = false; if (stream1 != null) stream1.Close(); if (stream2 != null) stream2.Close(); if (File.Exists(fileName)) { File.Delete(fileName); } return false; } finally { isDownload = false; stream2.Close(); stream1.Close(); } }后台下载功能
private void Cancel_Click(object sender, RoutedEventArgs e) { isDownload = true; progressbar.Value = 0.0; progressbar.Visibility = Visibility.Collapsed; this.confirm.IsEnabled = true; this.cancel.IsEnabled = false; }取消下载按钮
private void Confirm_Click(object sender, RoutedEventArgs e) { try { cancel.Visibility = Visibility.Visible; progressbar.Visibility = Visibility.Visible; // 重新加载按钮样式 confirm.Margin = new Thickness(40, 0, 0, 0); this.confirm.IsEnabled = false; this.cancel.IsEnabled = true; string resu = Tool.Get_cookie(configinfo.callLinkserviceurl + "/version/getReleaseVersion/1", null); if (resu != "") { JObject jo = (JObject)JsonConvert.DeserializeObject(resu); string code = jo["code"].ToString().ToUpper(); if (code == "200") { string url = jo["data"]["downloadUrl"].ToString(); string version = jo["data"]["versionFlag"].ToString(); if (url != null) { string filename = AppDomain.CurrentDomain.BaseDirectory + "NewVersion" + version + ".exe"; if (DownloadFile(url, filename, progressbar)) { MessageBox.Show("下载成功！"); // 将版本号存入json文件中 // Writejson(version); } } } } } catch (Exception) { // 更新失败 this.image.Visibility = Visibility.Visible; this.image1.Visibility = Visibility.Collapsed; Uri uri = new Uri(@"../Resources/fail.png", UriKind.Relative); this.image.Source = new BitmapImage(uri); this.inspect.Text = "更新检查失败"; } }下载按钮