> For the complete documentation index, see [llms.txt](https://boxlang.ortusbooks.com/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://boxlang.ortusbooks.com/boxlang-language/reference/built-in-functions/decision/isfileobject.md).

# IsFileObject

Determine whether the given object is a BoxLang File object.

## Method Signature

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

### Arguments

| Argument | Type  | Required | Description     | Default |
| -------- | ----- | -------- | --------------- | ------- |
| `object` | `any` | `true`   | Object to test. |         |

## Examples

### Check for a filestream-object

Checks if the fileObj is a filestream-object.

```java
filePath = expandPath( "./myfile.txt" );
fileObj = fileOpen( filePath );
writeOutput( isFileObject( fileObj ) );

```

Result: true

## Related

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


---

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