> 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/io/fileopen.md).

# FileOpen

Opens a file for reading or writing and returns a file object for future operations

## Method Signature

```
FileOpen(file=[string], mode=[string], charset=[string], seekable=[boolean])
```

### Arguments

| Argument   | Type      | Required | Description                                                                     | Default |
| ---------- | --------- | -------- | ------------------------------------------------------------------------------- | ------- |
| `file`     | `string`  | `true`   | The file to open.                                                               |         |
| `mode`     | `string`  | `false`  | The mode to open the file in. Defaults to "read".                               | `read`  |
| `charset`  | `string`  | `false`  | The character set to use when reading or writing the file. Defaults to "utf-8". | `utf-8` |
| `seekable` | `boolean` | `false`  | Whether the file should be opened as seekable. Defaults to false.               |         |

## Examples

### Opens a file, reads a line then closes it.

```java
// Open File
var fileObject = fileOpen( "/path/to/file.txt" );
// Perform Actions
try {
	// Read Line
	writeOutput( fileReadLine( fileObject ) );
}
// Error Handling
 catch (any ex) {
	// Report Exception
	writeDump( ex );
}finally {
	// Always Close
	// Close File
	fileClose( fileObject );
}

```

### Additional Examples

```java
myFile = fileOpen( "filepath/filename.ext" );
writeDump( myfile );

```

```java
// how to access the underlying resource provider info
f = "ram://demo.txt";
fileWrite( f, "demo" );
dump( f.getResource().getResourceProvider().getScheme() );
 // ram ( i.e. the resource provider type)

```

## Related

* [ContractPath](/boxlang-language/reference/built-in-functions/io/contractpath.md)
* [CreateTempDirectory](/boxlang-language/reference/built-in-functions/io/createtempdirectory.md)
* [CreateTempFile](/boxlang-language/reference/built-in-functions/io/createtempfile.md)
* [DirectoryCopy](/boxlang-language/reference/built-in-functions/io/directorycopy.md)
* [DirectoryCreate](/boxlang-language/reference/built-in-functions/io/directorycreate.md)
* [DirectoryDelete](/boxlang-language/reference/built-in-functions/io/directorydelete.md)
* [DirectoryExists](/boxlang-language/reference/built-in-functions/io/directoryexists.md)
* [DirectoryList](/boxlang-language/reference/built-in-functions/io/directorylist.md)
* [DirectoryMove](/boxlang-language/reference/built-in-functions/io/directorymove.md)
* [DirectoryRename](/boxlang-language/reference/built-in-functions/io/directoryrename.md)
* [ExpandPath](/boxlang-language/reference/built-in-functions/io/expandpath.md)
* [FileAppend](/boxlang-language/reference/built-in-functions/io/fileappend.md)
* [FileClose](/boxlang-language/reference/built-in-functions/io/fileclose.md)
* [FileCopy](/boxlang-language/reference/built-in-functions/io/filecopy.md)
* [FileDelete](/boxlang-language/reference/built-in-functions/io/filedelete.md)
* [FileExists](/boxlang-language/reference/built-in-functions/io/fileexists.md)
* [FileGetMimeType](/boxlang-language/reference/built-in-functions/io/filegetmimetype.md)
* [FileInfo](/boxlang-language/reference/built-in-functions/io/fileinfo.md)
* [FileIsEOF](/boxlang-language/reference/built-in-functions/io/fileiseof.md)
* [FileMove](/boxlang-language/reference/built-in-functions/io/filemove.md)
* [FileRead](/boxlang-language/reference/built-in-functions/io/fileread.md)
* [FileReadBinary](/boxlang-language/reference/built-in-functions/io/filereadbinary.md)
* [FileReadLine](/boxlang-language/reference/built-in-functions/io/filereadline.md)
* [FileSeek](/boxlang-language/reference/built-in-functions/io/fileseek.md)
* [FileSetAccessMode](/boxlang-language/reference/built-in-functions/io/filesetaccessmode.md)
* [FileSetAttribute](/boxlang-language/reference/built-in-functions/io/filesetattribute.md)
* [FileSetLastModified](/boxlang-language/reference/built-in-functions/io/filesetlastmodified.md)
* [FileSkipBytes](/boxlang-language/reference/built-in-functions/io/fileskipbytes.md)
* [FileWrite](/boxlang-language/reference/built-in-functions/io/filewrite.md)
* [FileWriteLine](/boxlang-language/reference/built-in-functions/io/filewriteline.md)
* [GetCanonicalPath](/boxlang-language/reference/built-in-functions/io/getcanonicalpath.md)
* [GetDirectoryFromPath](/boxlang-language/reference/built-in-functions/io/getdirectoryfrompath.md)
* [GetFileInfo](/boxlang-language/reference/built-in-functions/io/getfileinfo.md)
* [getTempFile](/boxlang-language/reference/built-in-functions/io/gettempfile.md)
* [PropertyFile](/boxlang-language/reference/built-in-functions/io/propertyfile.md)


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