NullReferenceException Class
The exception that is thrown when there is an attempt to dereference a null object reference.
Assembly: mscorlib (in mscorlib.dll)
The NullReferenceException type exposes the following members.
| Name | Description | |
|---|---|---|
![]() ![]() ![]() | NullReferenceException() | Initializes a new instance of the NullReferenceException class, setting the Message property of the new instance to a system-supplied message that describes the error, such as "The value 'null' was found where an instance of an object was required." This message takes into account the current system culture. |
![]() ![]() ![]() | NullReferenceException(String) | Initializes a new instance of the NullReferenceException class with a specified error message. |
![]() | NullReferenceException(SerializationInfo, StreamingContext) | Initializes a new instance of the NullReferenceException class with serialized data. |
![]() ![]() ![]() | NullReferenceException(String, Exception) | Initializes a new instance of the NullReferenceException class with a specified error message and a reference to the inner exception that is the cause of this exception. |
| Name | Description | |
|---|---|---|
![]() | Data | Gets a collection of key/value pairs that provide additional user-defined information about the exception. (Inherited from Exception.) |
![]() | HelpLink | Gets or sets a link to the help file associated with this exception. (Inherited from Exception.) |
![]() ![]() ![]() | HResult | Gets or sets HRESULT, a coded numerical value that is assigned to a specific exception. (Inherited from Exception.) |
![]() ![]() ![]() | InnerException | Gets the Exception instance that caused the current exception. (Inherited from Exception.) |
![]() ![]() ![]() | Message | Gets a message that describes the current exception. (Inherited from Exception.) |
![]() | Source | Gets or sets the name of the application or the object that causes the error. (Inherited from Exception.) |
![]() ![]() ![]() | StackTrace | Gets a string representation of the immediate frames on the call stack. (Inherited from Exception.) |
![]() | TargetSite | Gets the method that throws the current exception. (Inherited from Exception.) |
| Name | Description | |
|---|---|---|
![]() ![]() ![]() | Equals(Object) | Determines whether the specified Object is equal to the current Object. (Inherited from Object.) |
![]() ![]() ![]() | Finalize | Allows an object to try to free resources and perform other cleanup operations before it is reclaimed by garbage collection. (Inherited from Object.) |
![]() ![]() ![]() | GetBaseException | When overridden in a derived class, returns the Exception that is the root cause of one or more subsequent exceptions. (Inherited from Exception.) |
![]() ![]() ![]() | GetHashCode | Serves as a hash function for a particular type. (Inherited from Object.) |
![]() | GetObjectData | When overridden in a derived class, sets the SerializationInfo with information about the exception. (Inherited from Exception.) |
![]() ![]() ![]() | GetType | Gets the runtime type of the current instance. (Inherited from Exception.) In XNA Framework 3.0, this member is inherited from Object::GetType(). In Portable Class Library Portable Class Library, this member is inherited from Object::GetType(). |
![]() ![]() ![]() | MemberwiseClone | Creates a shallow copy of the current Object. (Inherited from Object.) |
![]() ![]() ![]() | ToString | Creates and returns a string representation of the current exception. (Inherited from Exception.) |
| Name | Description | |
|---|---|---|
![]() | SerializeObjectState | Occurs when an exception is serialized to create an exception state object that contains serialized data about the exception. (Inherited from Exception.) |
Note that applications throw the ArgumentNullException exception rather than the NullReferenceException exception discussed here.
The following Microsoft intermediate language (MSIL) instructions throw NullReferenceException :
callvirt
cpblk
cpobj
initblk
ldelem.<type>
ldelema
ldfld
ldflda
ldind.<type>
ldlen
stelem.<type>
stfld
stind.<type>
throw
unbox
NullReferenceException uses the HRESULT COR_E_NULLREFERENCE, which has the value 0x80004003.
For a list of initial property values for an instance of NullReferenceException, see the NullReferenceException constructors.
Windows 7, Windows Vista SP1 or later, Windows XP SP3, Windows XP SP2 x64 Edition, Windows Server 2008 (Server Core not supported), Windows Server 2008 R2 (Server Core supported with SP1 or later), Windows Server 2003 SP2
The .NET Framework does not support all versions of every platform. For a list of the supported versions, see .NET Framework System Requirements.






