我正在使用WebClient
类从Web服务器下载.exe文件。这是我用来下载文件的代码:
WebClient webClient = new WebClient();
webClient.DownloadProgressChanged += new DownloadProgressChangedEventHandler(webClient_DownloadProgressChanged);
webClient.DownloadDataAsync(new Uri("http://www.blah.com/calc.exe"));
我的应用程序有一个ProgressBar,它在回调(
webClient_DownloadProgressChanged
)中得到更新:private void webClient_DownloadProgressChanged(object sender, DownloadProgressChangedEventArgs e)
{
progressBar.Value = (int)e.BytesReceived;
}
我遇到的问题是必须动态设置进度栏的
Maximum
值。换句话说,在下载开始之前,我需要知道我正在下载的文件的大小。鉴于它是uri,有没有办法获取文件的大小(下载之前)?
最佳答案
尝试将最大大小设置为e.TotalBytesToReceive这样
private void webClient_DownloadProgressChanged(object sender, DownloadProgressChangedEventArgs e)
{
progressBar.Max = (int)e.TotalBytesToReceive;
progressBar.Value = (int)e.BytesReceived;
}