> 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/filewriteline.md).

# FileWriteLine

Writes a line of data to a file

## Method Signature

```
FileWriteLine(file=[any], data=[string])
```

### Arguments

| Argument | Type     | Required | Description                                 | Default |
| -------- | -------- | -------- | ------------------------------------------- | ------- |
| `file`   | `any`    | `true`   | An existing file object or a path to a file |         |
| `data`   | `string` | `true`   | The line of data to be written              |         |

## Examples

### Script Syntax

```java
myfile = fileOpen( "c:\temp\test1.txt", "write" );
fileWriteLine( myfile, "This line is new." );
fileClose( myfile );

```

### Additional Examples

```java
openFile = fileopen( filepath, "read" );
readfromfile = filereadline( openfile );
filewriteline( filepath, readfromfile );

```

## 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)
* [FileOpen](/boxlang-language/reference/built-in-functions/io/fileopen.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)
* [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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