我想知道为什么当我单击列表中的某个项目时，我的选择索引更改会触发两次。
这是我在 selectionindexchanged 中使用的代码
private void listBoxFolders_SelectionChanged(object sender, SelectionChangedEventArgs e)
{
// Taking the name of the folder to pass in the parameters
if ((Folder)listBoxFolders.SelectedItem != null)
{
folderTmp = (Folder)listBoxFolders.SelectedItem;
}
// Connection to the webservice to get the subfolders and also the files
WebClient wc = new WebClient();
wc.DownloadStringCompleted += new DownloadStringCompletedEventHandler(wc_DownloadStringCompleted2);
wc.DownloadStringAsync(new Uri("http://clients.uicentric.net/IISHostedCalcService/FilesService.svc/GetFoldersAndFiles?selectedFolder=" + folderTmp.Name));
}
这是在其中触发两次的方法：
public void wc_DownloadStringCompleted2(object sender, DownloadStringCompletedEventArgs e)
{
if (e.Error == null)
{
XDocument xdoc = XDocument.Parse(e.Result, LoadOptions.None);
XNamespace aNamespace = XNamespace.Get("http://schemas.datacontract.org/2004/07/System.IO");
try
{
// Retrieving the subfolders
var folders = from query in xdoc.Descendants(aNamespace.GetName("DirectoryInfo"))
select new Folder
{
Name = (string)query.Element("OriginalPath"),
};
_lFolders = new ObservableCollection<Folder>();
foreach (Folder f in folders)
{
LFolders.Add(f);
}
listBoxFolders.ItemsSource = LFolders;
listBoxFolders.DisplayMemberPath = "Name";
// Retrieving the files
var files = from query in xdoc.Descendants(aNamespace.GetName("FileInfo"))
select new File
{
Name = (string)query.Element("OriginalPath"),
};
_lFiles = new ObservableCollection<File>();
foreach (File f in files)
{
LFiles.Add(f);
}
listBoxFiles.ItemsSource = LFiles;
listBoxFiles.DisplayMemberPath = "Name";
listBoxFiles.SelectionChanged += new SelectionChangedEventHandler(listBoxFiles_SelectionChanged);
}
catch { }
}
}