VNRequestCompletionHandler Delegate
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A delegate that is called once for each feature detected in a VNRequest.
C#
public delegate void VNRequestCompletionHandler(VNRequest request, NSError error);type VNRequestCompletionHandler = delegate of VNRequest * NSError -> unit- error
- NSError
If not null, an error that occurred during vision processing.
Developers will typically downcast the to the expected subtype and retrieve relevant data from the downcast value:
C#
var findFacesRequest = new VNDetectFaceRectanglesRequest((request, error) =>
{
if (error != null)
{
HandleError(error);
}
else
{
var frs = request as VNDetectFaceRectanglesRequest;
// Assert frs == findFacesRequest
var rs = frs.GetResults<VNFaceObservation>();
foreach (var fo in rs)
{ // ... etc ...
| Produkt | Versioner |
|---|---|
| Xamarin iOS SDK | 12 |