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ArgumentNullException Class
 

The exception that is thrown when a null reference (Nothing in Visual Basic) is passed to a method that does not accept it as a valid argument.

Namespace:   System
Assembly:  mscorlib (in mscorlib.dll)

Inheritance Hierarchy
SystemObject
   SystemException
     SystemSystemException
       SystemArgumentException
        SystemArgumentNullException

Syntax
[SerializableAttribute]
[ComVisibleAttribute(true)]
public class ArgumentNullException : ArgumentException
[SerializableAttribute]
[ComVisibleAttribute(true)]
public ref class ArgumentNullException : ArgumentException
[<SerializableAttribute>]
[<ComVisibleAttribute(true)>]
type ArgumentNullException = 
    class
        inherit ArgumentException
    end
<SerializableAttribute>
<ComVisibleAttribute(True)>
Public Class ArgumentNullException
	Inherits ArgumentException
Constructors
NameDescription
System_CAPS_pubmethod ArgumentNullException

Initializes a new instance of the ArgumentNullException class.

System_CAPS_protmethod ArgumentNullException

Initializes a new instance of the ArgumentNullException class with serialized data.

System_CAPS_pubmethod ArgumentNullException

Initializes a new instance of the ArgumentNullException class with the name of the parameter that causes this exception.

System_CAPS_pubmethod ArgumentNullException

Initializes a new instance of the ArgumentNullException class with a specified error message and the exception that is the cause of this exception.

System_CAPS_pubmethod ArgumentNullException

Initializes an instance of the ArgumentNullException class with a specified error message and the name of the parameter that causes this exception.

Properties
NameDescription
System_CAPS_pubproperty

Gets a collection of key/value pairs that provide additional user-defined information about the exception.(Inherited from Exception.)

System_CAPS_pubproperty

Gets or sets a link to the help file associated with this exception.(Inherited from Exception.)

System_CAPS_pubproperty

Gets or sets HRESULT, a coded numerical value that is assigned to a specific exception.(Inherited from Exception.)

System_CAPS_pubproperty

Gets the Exception instance that caused the current exception.(Inherited from Exception.)

System_CAPS_pubproperty

Gets the error message and the parameter name, or only the error message if no parameter name is set.(Inherited from ArgumentException.)

System_CAPS_pubproperty

Gets the name of the parameter that causes this exception.(Inherited from ArgumentException.)

System_CAPS_pubproperty

Gets or sets the name of the application or the object that causes the error.(Inherited from Exception.)

System_CAPS_pubproperty

Gets a string representation of the immediate frames on the call stack.(Inherited from Exception.)

System_CAPS_pubproperty

Gets the method that throws the current exception.(Inherited from Exception.)

Methods
NameDescription
System_CAPS_pubmethod Equals

Determines whether the specified object is equal to the current object.(Inherited from Object.)

System_CAPS_protmethod Finalize

Allows an object to try to free resources and perform other cleanup operations before it is reclaimed by garbage collection.(Inherited from Object.)

System_CAPS_pubmethod GetBaseException

When overridden in a derived class, returns the Exception that is the root cause of one or more subsequent exceptions.(Inherited from Exception.)

System_CAPS_pubmethod GetHashCode

Serves as the default hash function. (Inherited from Object.)

System_CAPS_pubmethod GetObjectData

Sets the SerializationInfo object with the parameter name and additional exception information.(Inherited from ArgumentException.)

System_CAPS_pubmethod GetType

Gets the runtime type of the current instance.(Inherited from Exception.)

System_CAPS_protmethod MemberwiseClone

Creates a shallow copy of the current Object.(Inherited from Object.)

System_CAPS_pubmethod ToString

Creates and returns a string representation of the current exception.(Inherited from Exception.)

Events
NameDescription
System_CAPS_protevent SerializeObjectState

Occurs when an exception is serialized to create an exception state object that contains serialized data about the exception.(Inherited from Exception.)

Remarks

An ArgumentNullException exception is thrown when a method is invoked and at least one of the passed arguments is null but should never be null.

An ArgumentNullException exception is thrown at run time in the following two major circumstances, both of which reflect developer error:

  • An uninstantiated object is passed to a method. To prevent the error, instantiate the object.

  • An object returned from a method call is then passed as an argument to a second method, but the value of the original returned object is null. To prevent the error, check for a return value that is null and call the second method only if the return value is not null.

ArgumentNullException behaves identically to ArgumentException. It is provided so that application code can differentiate between exceptions caused by null arguments and exceptions caused by arguments that are not null. For errors caused by arguments that are not null, see ArgumentOutOfRangeException.

ArgumentNullException uses the HRESULT E_POINTER, which has the value 0x80004003.

For a list of initial property values for an instance of ArgumentNullException, see the ArgumentNullException constructors.

Version Information
Universal Windows Platform
Available since 8
.NET Framework
Available since 1.1
Portable Class Library
Supported in: portable .NET platforms
Silverlight
Available since 2.0
Windows Phone Silverlight
Available since 7.0
Windows Phone
Available since 8.1
Thread Safety

Any public static (Shared in Visual Basic) members of this type are thread safe. Any instance members are not guaranteed to be thread safe.

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