不明白啊,原码是这样的只有这一句不明白
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private void Page_Load(object sender, EventArgs e)
{
// extract from the querystring to path to scan
folderPath = Request.Params["Folder"];
// if the folder is not specified, or it is "/" (web server root)
// use the application's root folder as path
if (folderPath == null || folderPath=="/")
folderPath = Request.ApplicationPath.ToString();
// if the folder ends with "/", remove the last /
else if (folderPath.EndsWith("/"))
folderPath = folderPath.Substring(0, folderPath.Length-1);
// write the physical and virtual path
FolderDescription.Text = "Virtual folder: " + folderPath +
"<br>Physical folder: " + Server.MapPath(folderPath);
// actually scan the specified folder