# IsNull

Determine whether a given value or variable reference is null.

## Method Signature

```
IsNull(object=[any])
```

### Arguments

| Argument | Type  | Required | Description             | Default |
| -------- | ----- | -------- | ----------------------- | ------- |
| `object` | `any` | `true`   | Value to test for null. |         |

## Examples

### isNull Example

Returns true if the given object is null or the given expressions evaluates to null; Returns false is otherwise.

[Run Example](https://try.boxlang.io/?code=eJzLLPYrzcnRUMhKLEt0Tiwu0VBQygMKKOkoKCkpaCpoWnMBAMSRCZs%3D)

```java
isNull( javaCast( "null", "" ) );

```

Result: true

### Additional Examples

```java
v1 = "test";
writeDump( isnull( v1 ) ); // false
v2; // Defining empty variable or v2=nullValue();
writeDump( isnull( v2 ) );
 // true

```

## Related

* [ArrayIsEmpty](https://boxlang.ortusbooks.com/boxlang-language/reference/built-in-functions/decision/arrayisempty)
* [arrayIsEmpty](https://github.com/ortus-boxlang/boxlang-docs/blob/v1.x/boxlang-language/reference/built-in-functions/decision/arrayIsEmpty.md)
* [Attempt](https://boxlang.ortusbooks.com/boxlang-language/reference/built-in-functions/decision/attempt)
* [IsArray](https://boxlang.ortusbooks.com/boxlang-language/reference/built-in-functions/decision/isarray)
* [IsBinary](https://boxlang.ortusbooks.com/boxlang-language/reference/built-in-functions/decision/isbinary)
* [IsBoolean](https://boxlang.ortusbooks.com/boxlang-language/reference/built-in-functions/decision/isboolean)
* [IsClosure](https://boxlang.ortusbooks.com/boxlang-language/reference/built-in-functions/decision/isclosure)
* [IsCustomFunction](https://boxlang.ortusbooks.com/boxlang-language/reference/built-in-functions/decision/iscustomfunction)
* [IsDate](https://boxlang.ortusbooks.com/boxlang-language/reference/built-in-functions/decision/isdate)
* [IsDateObject](https://boxlang.ortusbooks.com/boxlang-language/reference/built-in-functions/decision/isdateobject)
* [IsDebugMode](https://boxlang.ortusbooks.com/boxlang-language/reference/built-in-functions/decision/isdebugmode)
* [IsDefined](https://boxlang.ortusbooks.com/boxlang-language/reference/built-in-functions/decision/isdefined)
* [IsEmpty](https://boxlang.ortusbooks.com/boxlang-language/reference/built-in-functions/decision/isempty)
* [IsFileObject](https://boxlang.ortusbooks.com/boxlang-language/reference/built-in-functions/decision/isfileobject)
* [IsIPv6](https://boxlang.ortusbooks.com/boxlang-language/reference/built-in-functions/decision/isipv6)
* [IsJSON](https://boxlang.ortusbooks.com/boxlang-language/reference/built-in-functions/decision/isjson)
* [IsLeapYear](https://boxlang.ortusbooks.com/boxlang-language/reference/built-in-functions/decision/isleapyear)
* [IsLocalHost](https://boxlang.ortusbooks.com/boxlang-language/reference/built-in-functions/decision/islocalhost)
* [IsNumeric](https://boxlang.ortusbooks.com/boxlang-language/reference/built-in-functions/decision/isnumeric)
* [IsNumericDate](https://boxlang.ortusbooks.com/boxlang-language/reference/built-in-functions/decision/isnumericdate)
* [IsObject](https://boxlang.ortusbooks.com/boxlang-language/reference/built-in-functions/decision/isobject)
* [IsQuery](https://boxlang.ortusbooks.com/boxlang-language/reference/built-in-functions/decision/isquery)
* [IsSimpleValue](https://boxlang.ortusbooks.com/boxlang-language/reference/built-in-functions/decision/issimplevalue)
* [IsStruct](https://boxlang.ortusbooks.com/boxlang-language/reference/built-in-functions/decision/isstruct)
* [IsValid](https://boxlang.ortusbooks.com/boxlang-language/reference/built-in-functions/decision/isvalid)
* [IsXML](https://boxlang.ortusbooks.com/boxlang-language/reference/built-in-functions/decision/isxml)
* [IsXmlAttribute](https://boxlang.ortusbooks.com/boxlang-language/reference/built-in-functions/decision/isxmlattribute)
* [IsXMLDoc](https://boxlang.ortusbooks.com/boxlang-language/reference/built-in-functions/decision/isxmldoc)
* [IsXMLElem](https://boxlang.ortusbooks.com/boxlang-language/reference/built-in-functions/decision/isxmlelem)
* [IsXMLNode](https://boxlang.ortusbooks.com/boxlang-language/reference/built-in-functions/decision/isxmlnode)
* [IsXMLRoot](https://boxlang.ortusbooks.com/boxlang-language/reference/built-in-functions/decision/isxmlroot)
* [LSIsNumeric](https://boxlang.ortusbooks.com/boxlang-language/reference/built-in-functions/decision/lsisnumeric)
* [structIsEmpty](https://boxlang.ortusbooks.com/boxlang-language/reference/built-in-functions/decision/structisempty)


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