> 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/string/stringmap.md).

# StringMap

Iterates over all elements in a string and returns a new mapped string

## Method Signature

```
StringMap(list=[string], callback=[function:Function], delimiter=[string], includeEmptyFields=[boolean], multiCharacterDelimiter=[boolean], parallel=[boolean], maxThreads=[any], virtual=[boolean])
```

### Arguments

| Argument                  | Type                | Required | Description                                                 | Default |
| ------------------------- | ------------------- | -------- | ----------------------------------------------------------- | ------- |
| `list`                    | `string`            | `true`   |                                                             |         |
| `callback`                | `function:Function` | `true`   | The callback which returns a boolean and filters the string |         |
| `delimiter`               | `string`            | `false`  |                                                             | `,`     |
| `includeEmptyFields`      | `boolean`           | `false`  |                                                             | `false` |
| `multiCharacterDelimiter` | `boolean`           | `false`  |                                                             | `false` |
| `parallel`                | `boolean`           | `false`  |                                                             | `false` |
| `maxThreads`              | `any`               | `false`  |                                                             |         |
| `virtual`                 | `boolean`           | `false`  |                                                             | `false` |

## Examples

### Full function

Map each element of the string to a new value.

[Run Example](https://try.boxlang.io/?code=eJw1jTEKAjEQRWtzis9WE7S3CCt4ALHwBNk4rgMhhskEEfHuq6jtezxeZjPWhhFDnNKZL%2FMQXMq31pXfkLAvD0ip8Bh3eLqVsnUtSNeohNiSCP38Glv44F7B3VWMj91qN8LJVMp8iJWQv7MN%2FgP%2FCRae5Skm)

```java
letters = "abcdefg";
closure = ( Any inp ) => {
	return char( ascii( inp ) + 7 );
};
writeOutput( StringMap( letters, closure ) );

```

Result: hijklmn

### Member function

Map each element of the string to a new value.

```java
letters = "abcdefg";
closure = ( Any inp ) => {
	return char( ascii( inp ) + 7 );
};
writeOutput( letters.map( closure ) );

```

Result: hijklmn

### Additional Examples

[Run Example](https://try.boxlang.io/?code=eJzLrQwuKcrMS1ewVVDySM3JyVcIzy%2FKSVGy5krOyS8uLUoFSmgoOOZVKpQl5ihoKtjaKVRzcRallpQW5SlogMTUFJQSlTStuWqtucqLMktSXUpzCzQUIKb6JgKZuVArdBRgRmoqANUDADxKJig%3D)

```java
myString = "Hello World";
closure = ( Any val ) => {
	return (val & "a");
};
writeDump( StringMap( myString, closure ) );

```

## Related

* [Ascii](/boxlang-language/reference/built-in-functions/string/ascii.md)
* [CamelCase](/boxlang-language/reference/built-in-functions/string/camelcase.md)
* [Char](/boxlang-language/reference/built-in-functions/string/char.md)
* [CharsetDecode](/boxlang-language/reference/built-in-functions/string/charsetdecode.md)
* [CharsetEncode](/boxlang-language/reference/built-in-functions/string/charsetencode.md)
* [Compare](/boxlang-language/reference/built-in-functions/string/compare.md)
* [CompareNoCase](/boxlang-language/reference/built-in-functions/string/comparenocase.md)
* [Find](/boxlang-language/reference/built-in-functions/string/find.md)
* [FindNoCase](/boxlang-language/reference/built-in-functions/string/findnocase.md)
* [FindOneOf](/boxlang-language/reference/built-in-functions/string/findoneof.md)
* [Insert](/boxlang-language/reference/built-in-functions/string/insert.md)
* [JSStringFormat](/boxlang-language/reference/built-in-functions/string/jsstringformat.md)
* [Justify](/boxlang-language/reference/built-in-functions/string/justify.md)
* [KebabCase](/boxlang-language/reference/built-in-functions/string/kebabcase.md)
* [LCase](/boxlang-language/reference/built-in-functions/string/lcase.md)
* [Left](/boxlang-language/reference/built-in-functions/string/left.md)
* [ListReduce](/boxlang-language/reference/built-in-functions/string/listreduce.md)
* [LJustify](/boxlang-language/reference/built-in-functions/string/ljustify.md)
* [LTrim](/boxlang-language/reference/built-in-functions/string/ltrim.md)
* [Mid](/boxlang-language/reference/built-in-functions/string/mid.md)
* [ParagraphFormat](/boxlang-language/reference/built-in-functions/string/paragraphformat.md)
* [PascalCase](/boxlang-language/reference/built-in-functions/string/pascalcase.md)
* [QueryStringToStruct](/boxlang-language/reference/built-in-functions/string/querystringtostruct.md)
* [ReEscape](/boxlang-language/reference/built-in-functions/string/reescape.md)
* [ReFind](/boxlang-language/reference/built-in-functions/string/refind.md)
* [reFindNoCase](/boxlang-language/reference/built-in-functions/string/refindnocase.md)
* [ReMatch](/boxlang-language/reference/built-in-functions/string/rematch.md)
* [reMatchNoCase](/boxlang-language/reference/built-in-functions/string/rematchnocase.md)
* [RemoveChars](/boxlang-language/reference/built-in-functions/string/removechars.md)
* [RepeatString](/boxlang-language/reference/built-in-functions/string/repeatstring.md)
* [Replace](/boxlang-language/reference/built-in-functions/string/replace.md)
* [ReplaceList](/boxlang-language/reference/built-in-functions/string/replacelist.md)
* [ReplaceListNoCase](/boxlang-language/reference/built-in-functions/string/replacelistnocase.md)
* [ReplaceNoCase](/boxlang-language/reference/built-in-functions/string/replacenocase.md)
* [ReReplace](/boxlang-language/reference/built-in-functions/string/rereplace.md)
* [reReplaceNoCase](/boxlang-language/reference/built-in-functions/string/rereplacenocase.md)
* [Reverse](/boxlang-language/reference/built-in-functions/string/reverse.md)
* [Right](/boxlang-language/reference/built-in-functions/string/right.md)
* [RJustify](/boxlang-language/reference/built-in-functions/string/rjustify.md)
* [RTrim](/boxlang-language/reference/built-in-functions/string/rtrim.md)
* [Slugify](/boxlang-language/reference/built-in-functions/string/slugify.md)
* [SnakeCase](/boxlang-language/reference/built-in-functions/string/snakecase.md)
* [SpanExcluding](/boxlang-language/reference/built-in-functions/string/spanexcluding.md)
* [SpanIncluding](/boxlang-language/reference/built-in-functions/string/spanincluding.md)
* [SQLPrettify](/boxlang-language/reference/built-in-functions/string/sqlprettify.md)
* [StringBind](/boxlang-language/reference/built-in-functions/string/stringbind.md)
* [StringEach](/boxlang-language/reference/built-in-functions/string/stringeach.md)
* [StringEndsWith](/boxlang-language/reference/built-in-functions/string/stringendswith.md)
* [StringEndsWithNoCase](/boxlang-language/reference/built-in-functions/string/stringendswithnocase.md)
* [StringEvery](/boxlang-language/reference/built-in-functions/string/stringevery.md)
* [StringFilter](/boxlang-language/reference/built-in-functions/string/stringfilter.md)
* [StringReduce](/boxlang-language/reference/built-in-functions/string/stringreduce.md)
* [StringReduceRight](/boxlang-language/reference/built-in-functions/string/stringreduceright.md)
* [StringSome](/boxlang-language/reference/built-in-functions/string/stringsome.md)
* [StringSort](/boxlang-language/reference/built-in-functions/string/stringsort.md)
* [StringStartsWith](/boxlang-language/reference/built-in-functions/string/stringstartswith.md)
* [StringStartsWithNoCase](/boxlang-language/reference/built-in-functions/string/stringstartswithnocase.md)
* [StripCR](/boxlang-language/reference/built-in-functions/string/stripcr.md)
* [Trim](/boxlang-language/reference/built-in-functions/string/trim.md)
* [UCase](/boxlang-language/reference/built-in-functions/string/ucase.md)
* [UCFirst](/boxlang-language/reference/built-in-functions/string/ucfirst.md)
* [Val](/boxlang-language/reference/built-in-functions/string/val.md)
* [Wrap](/boxlang-language/reference/built-in-functions/string/wrap.md)
* [YesNoFormat](/boxlang-language/reference/built-in-functions/string/yesnoformat.md)


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