NSError Class

Definition

Encapsulates an error.

[Foundation.Register("NSError", true)]
public class NSError : Foundation.NSObject, Foundation.INSCopying, Foundation.INSSecureCoding, IDisposable
type NSError = class
    inherit NSObject
    interface INSCoding
    interface INativeObject
    interface IDisposable
    interface INSCopying
    interface INSSecureCoding
Inheritance
NSError
Attributes
Implements

Remarks

NSError objects wrap both error domains, an error code and an optional error payload into one.   The error domain is used to classify the error (typically, there is an error domain per susbsystem).   There are several static properties in the NSError class that represent some common domains like the CocoaErrorDomain or the CFNetworkErrorDomain.

NSErrors can be serialized.

You can create an NSError with a domain by providing both parameters.  The following example shows how to do this, and passes a payload:

var payload = NSDictionary.FromObjectsAndKeys (new object [] {1,2,3,4});

When creating the error with a payload, you can provide a number of optional elements that provide the user with more information.   You should provide this information on the NSDictionary with the keys defined in this class like LocalizedFailureErrorKeyP:Foundation.NSError.FilePathErrorKey, HelpAnchorErrorKeyLocalizedDescriptionKeyLocalizedFailureReasonErrorKeyLocalizedRecoveryOptionsErrorKeyLocalizedRecoverySuggestionErrorKeyP:Foundation.NSError.StringEncodingErrorKey, UnderlyingErrorKey and P:Foundation.NSError.UrlErrorKey.

For example:

var userInfo = new NSDictionary (NSError.LocalizedDescriptionKey, "Error while parsing GeoJSON”);

The LocalizedDescription property will return the above value.

Constructors

NSError()

Do not use the Default Constructor unless you are dealing with a low-level API that will initialize the object for you.

NSError(IntPtr)

A constructor used when creating managed representations of unmanaged objects; Called by the runtime.

NSError(NSCoder)

A constructor that initializes the object from the data stored in the unarchiver object.

NSError(NSObjectFlag)

Constructor to call on derived classes to skip initialization and merely allocate the object.

NSError(NSString, nint)

A constructor that initializes the object with a specified domain and an error code.

NSError(NSString, nint, NSDictionary)

Properties

CFNetworkErrorDomain

The CFNetwork error domain.

Class (Inherited from NSObject)
ClassHandle

The handle for this class.

CocoaErrorDomain

The Cocoa error domain.

Code

The error code in this NSError

CoreLocationErrorDomain

The CoreLocation error domain.

CoreMotionErrorDomain

The CoreMotion error domain.

DebugDescription

A developer-meaningful description of this object.

(Inherited from NSObject)
DebugDescriptionErrorKey
Description

Description of the object, the Objective-C version of ToString.

(Inherited from NSObject)
Domain

The domain associated with this error.

EABluetoothAccessoryPickerErrorDomain

Represents the value associated with the constant EABluetoothAccessoryPickerErrorDomain

FilePathErrorKey

Standard key to use in the userInfo payload for associating a file path with the error.

Handle

Handle (pointer) to the unmanaged object representation.

(Inherited from NSObject)
HelpAnchor

Returns the help anchor that was associated with this error (the payload contained a HelpAnchorErrorKey)

HelpAnchorErrorKey

Standard key to use in the userInfo payload for associating a hint to provide to the user.

IsDirectBinding (Inherited from NSObject)
IsProxy (Inherited from NSObject)
LocalizedDescription

Returns a localized description of the error.

LocalizedDescriptionKey

Standard key to use in the userInfo payload for associating a localized description of the problem to provide to the user.

LocalizedFailureErrorKey
LocalizedFailureReason
LocalizedFailureReasonErrorKey

Represents the value associated with the constant NSLocalizedFailureReasonErrorKey

LocalizedRecoveryOptions
LocalizedRecoveryOptionsErrorKey

Represents the value associated with the constant NSLocalizedRecoveryOptionsErrorKey

LocalizedRecoverySuggestion
LocalizedRecoverySuggestionErrorKey

Represents the value associated with the constant NSLocalizedRecoverySuggestionErrorKey

MachErrorDomain

Represents the value associated with the constant NSMachErrorDomain

MapKitErrorDomain

Represents the value associated with the constant MKErrorDomain

NSNetServicesErrorDomain

Represents the value associated with the constant NSNetServicesErrorDomain

NSStreamSocketSSLErrorDomain

Represents the value associated with the constant NSStreamSocketSSLErrorDomain

NSStreamSOCKSErrorDomain

Represents the value associated with the constant NSStreamSOCKSErrorDomain

NSUrlErrorDomain

Represents the value associated with the constant NSURLErrorDomain

OsStatusErrorDomain

Represents the value associated with the constant NSOSStatusErrorDomain

PosixErrorDomain

Represents the value associated with the constant NSPOSIXErrorDomain

RecoveryAttempterErrorKey

Represents the value associated with the constant NSRecoveryAttempterErrorKey

RetainCount

Returns the current Objective-C retain count for the object.

(Inherited from NSObject)
Self (Inherited from NSObject)
StringEncodingErrorKey

Represents the value associated with the constant NSStringEncodingErrorKey

Superclass (Inherited from NSObject)
SuperHandle

Handle used to represent the methods in the base class for this NSObject.

(Inherited from NSObject)
UnderlyingErrorKey

Represents the value associated with the constant NSUnderlyingErrorKey

UrlErrorKey

Represents the value associated with the constant NSURLErrorKey

UserInfo

Returns the associated user-defined payload.

WatchKitErrorDomain

The WatchKit error domain.

Zone (Inherited from NSObject)

Methods

AddObserver(NSObject, NSString, NSKeyValueObservingOptions, IntPtr)

Registers an object for being observed externally (using NSString keyPath).   Observed changes are dispatched to the observer’s object ObserveValue(NSString, NSObject, NSDictionary, IntPtr) method.

(Inherited from NSObject)
AddObserver(NSObject, String, NSKeyValueObservingOptions, IntPtr)

Registers an object for being observed externally (using string keyPath).   Observed changes are dispatched to the observer’s object ObserveValue(NSString, NSObject, NSDictionary, IntPtr) method.

(Inherited from NSObject)
AddObserver(NSString, NSKeyValueObservingOptions, Action<NSObservedChange>)

Registers an object for being observed externally using an arbitrary method.

(Inherited from NSObject)
AddObserver(String, NSKeyValueObservingOptions, Action<NSObservedChange>)

Registers an object for being observed externally using an arbitrary method.

(Inherited from NSObject)
AwakeFromNib()

Called after the object has been loaded from the nib file. Overriders must call base.AwakeFromNib().

(Inherited from NSObject)
BeginInvokeOnMainThread(Action) (Inherited from NSObject)
BeginInvokeOnMainThread(Selector, NSObject)

Invokes asynchrously the specified code on the main UI thread.

(Inherited from NSObject)
Bind(NSString, NSObject, String, NSDictionary) (Inherited from NSObject)
Bind(String, NSObject, String, NSDictionary) (Inherited from NSObject)
BindingInfo(String) (Inherited from NSObject)
BindingOptionDescriptions(String) (Inherited from NSObject)
BindingValueClass(String) (Inherited from NSObject)
CommitEditing() (Inherited from NSObject)
CommitEditing(NSObject, Selector, IntPtr) (Inherited from NSObject)
ConformsToProtocol(IntPtr)

Invoked to determine if this object implements the specified protocol.

(Inherited from NSObject)
Copy()

Performs a copy of the underlying Objective-C object.

(Inherited from NSObject)
Copy(NSZone)

Performs a copy of the underlying Objective-C object.

DangerousAutorelease() (Inherited from NSObject)
DangerousRelease() (Inherited from NSObject)
DangerousRetain() (Inherited from NSObject)
DidChange(NSKeyValueChange, NSIndexSet, NSString)

Indicates a change occurred to the indexes for a to-many relationship.

(Inherited from NSObject)
DidChange(NSString, NSKeyValueSetMutationKind, NSSet) (Inherited from NSObject)
DidChangeValue(String)

Indicates that a change occurred on the specified key.

(Inherited from NSObject)
Dispose()

Releases the resources used by the NSObject object.

(Inherited from NSObject)
Dispose(Boolean)

Releases the resources used by the NSObject object.

(Inherited from NSObject)
DoesNotRecognizeSelector(Selector)

Indicates that this object does not recognize the specified selector.

(Inherited from NSObject)
EncodeTo(NSCoder)

Encodes the state of the object on the provided encoder

Equals(NSObject) (Inherited from NSObject)
Equals(Object) (Inherited from NSObject)
ExposedBindings() (Inherited from NSObject)
FromDomain(NSString, nint)

Creates an NSError instance from a given domain and code.

FromDomain(NSString, nint, NSDictionary)
GetBindingInfo(NSString) (Inherited from NSObject)
GetBindingOptionDescriptions(NSString) (Inherited from NSObject)
GetBindingValueClass(NSString) (Inherited from NSObject)
GetDictionaryOfValuesFromKeys(NSString[])

Retrieves the values of the specified keys.

(Inherited from NSObject)
GetFileProviderError(INSFileProviderItem)
GetFileProviderError(String)
GetHashCode()

Generates a hash code for the current instance.

(Inherited from NSObject)
GetMethodForSelector(Selector) (Inherited from NSObject)
GetNativeField(String) (Inherited from NSObject)
GetNativeHash() (Inherited from NSObject)
GetUserInfoValueProvider(String)
Init() (Inherited from NSObject)
InitializeHandle(IntPtr) (Inherited from NSObject)
InitializeHandle(IntPtr, String) (Inherited from NSObject)
Invoke(Action, Double) (Inherited from NSObject)
Invoke(Action, TimeSpan) (Inherited from NSObject)
InvokeOnMainThread(Action) (Inherited from NSObject)
InvokeOnMainThread(Selector, NSObject)

Invokes synchrously the specified code on the main UI thread.

(Inherited from NSObject)
IsEqual(NSObject) (Inherited from NSObject)
IsKindOfClass(Class) (Inherited from NSObject)
IsMemberOfClass(Class) (Inherited from NSObject)
MarkDirty()

Promotes a regular peer object (IsDirectBinding is true) into a toggleref object.

(Inherited from NSObject)
MutableCopy()

Creates a mutable copy of the specified NSObject.

(Inherited from NSObject)
ObjectDidEndEditing(NSObject) (Inherited from NSObject)
ObserveValue(NSString, NSObject, NSDictionary, IntPtr)

Indicates that the value at the specified keyPath relative to this object has changed.

(Inherited from NSObject)
PerformSelector(Selector) (Inherited from NSObject)
PerformSelector(Selector, NSObject) (Inherited from NSObject)
PerformSelector(Selector, NSObject, Double)

Invokes the selector on the current instance and if the obj is not null, it passes this as its single parameter.

(Inherited from NSObject)
PerformSelector(Selector, NSObject, Double, NSString[]) (Inherited from NSObject)
PerformSelector(Selector, NSObject, NSObject) (Inherited from NSObject)
PerformSelector(Selector, NSThread, NSObject, Boolean) (Inherited from NSObject)
PerformSelector(Selector, NSThread, NSObject, Boolean, NSString[]) (Inherited from NSObject)
PrepareForInterfaceBuilder() (Inherited from NSObject)
RemoveObserver(NSObject, NSString)

Stops the specified observer from receiving further notifications of changed values for the specified keyPath.

(Inherited from NSObject)
RemoveObserver(NSObject, NSString, IntPtr)

Stops the specified observer from receiving further notifications of changed values for the specified keyPath and context.

(Inherited from NSObject)
RemoveObserver(NSObject, String)

Stops the specified observer from receiving further notifications of changed values for the specified keyPath.

(Inherited from NSObject)
RemoveObserver(NSObject, String, IntPtr)

Stops the specified observer from receiving further notifications of changed values for the specified keyPath and context.

(Inherited from NSObject)
RespondsToSelector(Selector)

Whether this object recognizes the specified selector.

(Inherited from NSObject)
SetNativeField(String, NSObject) (Inherited from NSObject)
SetNilValueForKey(NSString)

Sets the value of the specified key to null.

(Inherited from NSObject)
SetUserInfoValueProvider(String, NSErrorUserInfoValueProvider)
SetValueForKey(NSObject, NSString)

Sets the value of the property specified by the key to the specified value.

(Inherited from NSObject)
SetValueForKeyPath(IntPtr, NSString)

A constructor used when creating managed representations of unmanaged objects; Called by the runtime.

(Inherited from NSObject)
SetValueForKeyPath(NSObject, NSString)

Sets the value of a property that can be reached using a keypath.

(Inherited from NSObject)
SetValueForUndefinedKey(NSObject, NSString)

Indicates an attempt to write a value to an undefined key. If not overridden, raises an NSUndefinedKeyException.

(Inherited from NSObject)
SetValuesForKeysWithDictionary(NSDictionary)

Sets the values of this NSObject to those in the specified dictionary.

(Inherited from NSObject)
ToString()

Returns a string representation of the value of the current instance.

Unbind(NSString) (Inherited from NSObject)
Unbind(String) (Inherited from NSObject)
ValueForKey(NSString)

Returns the value of the property associated with the specified key.

(Inherited from NSObject)
ValueForKeyPath(NSString)

Returns the value of a property that can be reached using a keypath.

(Inherited from NSObject)
ValueForUndefinedKey(NSString)

Indicates an attempt to read a value of an undefined key. If not overridden, raises an NSUndefinedKeyException.

(Inherited from NSObject)
WillChange(NSKeyValueChange, NSIndexSet, NSString)

Indicates that the values of the specified indices in the specified key are about to change.

(Inherited from NSObject)
WillChange(NSString, NSKeyValueSetMutationKind, NSSet) (Inherited from NSObject)
WillChangeValue(String)

Indicates that the value of the specified key is about to change.

(Inherited from NSObject)

Extension Methods

ObjectDidBeginEditing(NSObject, INSEditor)
ObjectDidEndEditing(NSObject, INSEditor)
GetValidModes(NSObject, NSFontPanel)
ValidateToolbarItem(NSObject, NSToolbarItem)
GetDebugDescription(INSObjectProtocol)
AcceptsPreviewPanelControl(NSObject, QLPreviewPanel)
BeginPreviewPanelControl(NSObject, QLPreviewPanel)
EndPreviewPanelControl(NSObject, QLPreviewPanel)
GetAccessibilityCustomRotors(NSObject)

Gets the array of UIAccessibilityCustomRotor objects appropriate for this object.

SetAccessibilityCustomRotors(NSObject, UIAccessibilityCustomRotor[])

Sets the array of UIAccessibilityCustomRotor objects appropriate for this object.

Applies to

See also