问题
Hello legendary coders.
Flowing by my previous question I tried to use user32.dll
in windows universal application (UWP) in C# language but I encountered an error while trying to use the method I imported from that .dll
here is my code:
[DllImport("user32.dll")]
public static extern bool LockWorkStation();
private async void btnLock_Click(object sender, RoutedEventArgs e)
{
string path;
if (Images.TryGetValue(selectedRadioButton.Name, out path))
{
StorageFile file = await StorageFile.GetFileFromPathAsync(path);
await LockScreen.SetImageFileAsync(file);
if (!LockWorkStation())
throw new Exception(Marshal.GetLastWin32Error().ToString());
}
}
as you can see I imported LockWorkStation()
mthod from user32.dll
and I used it in the event listener of a button. the Images
is a Dictionary<string,string>
and every thing is Fine unless the call to method LockWorkStation()
it always return false
and so the thrown error is 1008 I mentioned it in the Title The question is Why? and how can I assign a token?
Note: any way,any way to lock the screen is admirable.
回答1:
So after searching a lot and being hopeless from directly lock the screen from the universal windows application platform I send a web request to a local web server and I made that web server to use the user32.dll
and lock the screen.
here is the code in the UWP app:
try
{
HttpClient httpClient = new HttpClient();
Uri uri = new Uri("http://localhost:8080/lock/");
HttpStringContent content = new HttpStringContent(
"{ \"pass\": \"theMorteza@1378App\" }",
UnicodeEncoding.Utf8,
"application/json");
HttpResponseMessage httpResponseMessage = await httpClient.PostAsync(
uri,
content);
httpResponseMessage.EnsureSuccessStatusCode();
}
catch (Exception ex)
{
throw ex;
}
and there is the code in the web server:
[DllImport("user32.dll")]
public static extern bool LockWorkStation();
private static string LockTheScreen(HttpListenerRequest request)
{
var inputStream = request.InputStream;
try
{
using (StreamReader sr = new StreamReader(inputStream))
{
JToken pass = JToken.Parse(sr.ReadToEnd());
if (pass.Value<string>("pass") == "theMorteza@1378App")
{
LockWorkStation();
}
}
}
catch (Exception)
{
return "fail";
}
return "fail";
}
Note: you can find how to make a simple web server here
But: you must install the web server and grant it's access for users.
来源:https://stackoverflow.com/questions/57737883/problem-using-user32-dll-in-c-sharp-error-1008-an-attempt-was-made-to-reference