)我将xml文件从互联网下载到内存电话..我想查看是否可以通过互联网连接进行下载,如果没有则发送消息。如果不是,我想看看内存中是否已存在xml文件..如果存在,则应用程序不会进行下载。
我有以下代码:
public MainPage()
{
InitializeComponent();
WebClient downloader = new WebClient();
Uri xmlUri = new Uri("http://dl.dropbox.com/file_xml.xml", UriKind.Absolute);
downloader.DownloadStringCompleted += new DownloadStringCompletedEventHandler(Downloaded);
downloader.DownloadStringAsync(xmlUri);
}
void Downloaded(object sender, DownloadStringCompletedEventArgs e)
{
if (e.Result == null || e.Error != null)
{
MessageBox.Show("There was an error downloading the xml-file");
}
else
{
IsolatedStorageFile myIsolatedStorage = IsolatedStorageFile.GetUserStoreForApplication();
using (StreamWriter writeFile = new StreamWriter(new IsolatedStorageFileStream("xml_file.xml", FileMode.Create, FileAccess.Write, myIsolatedStorage)))
{
string xml_file = e.Result.ToString();
writeFile.WriteLine(xml_file);
writeFile.Close();
}
}
}
}
答案 0 :(得分:3)
NetworkInterface.GetIsNetworkAvailable()方法可以告诉你:
using System.Net.NetworkInformation;
...
if (NetworkInterface.GetIsNetworkAvailable())
{
// do network-bound stuff
}
else
{
// notify the user that there is no network connection
}