> For the complete documentation index, see [llms.txt](https://docs.servoy.com/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://docs.servoy.com/reference/servoycore/dev-api/js-lib/set.md).

# Set

## Overview

The Set object lets you store unique values of any type, whether primitive values or object references. For more information see: [Set (MDN)](https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Set).

## Properties Summarized

| Type                                                     | Name          | Summary                                                                    |
| -------------------------------------------------------- | ------------- | -------------------------------------------------------------------------- |
| [Number](/reference/servoycore/dev-api/js-lib/number.md) | [size](#size) | The size accessor property returns the number of elements in a Set object. |

## Methods Summarized

| Type                                                         | Name                                                              | Summary                                                                                                                                         |
| ------------------------------------------------------------ | ----------------------------------------------------------------- | ----------------------------------------------------------------------------------------------------------------------------------------------- |
| [Set](/reference/servoycore/dev-api/js-lib/set.md)           | [add(value)](#add-value)                                          | The set() method adds or updates an entry in a Set object with a specified key and a value.                                                     |
| void                                                         | [clear()](#clear)                                                 | The clear() method removes all elements from a Set object.                                                                                      |
| [Boolean](/reference/servoycore/dev-api/js-lib/boolean.md)   | [delete(value)](#delete-value)                                    | The delete() method removes the specified element from a Set object by key.                                                                     |
| [Iterator](/reference/servoycore/dev-api/js-lib/iterator.md) | [entries()](#entries)                                             | The entries() method returns a new iterator object that contains the \[key, value] pairs for each element in the Set object in insertion order. |
| void                                                         | [forEach(callback, thisArgument)](#foreach-callback-thisargument) | The forEach() method executes a provided function once for each value in the Set object, in insertion order.                                    |
| [Boolean](/reference/servoycore/dev-api/js-lib/boolean.md)   | [has(key)](#has-key)                                              | The has() method returns a boolean indicating whether an element with the specified value exists in a Set object or not.                        |
| [Iterator](/reference/servoycore/dev-api/js-lib/iterator.md) | [keys()](#keys)                                                   | The keys() method returns a new iterator object that contains the keys for each element in the Set object in insertion order.                   |
| [Iterator](/reference/servoycore/dev-api/js-lib/iterator.md) | [values()](#values)                                               | The values() method returns a new iterator object that contains the values for each element in the Set object in insertion order.               |

## Properties Detailed

### size

The size accessor property returns the number of elements in a Set object.

**Type**\
[Number](/reference/servoycore/dev-api/js-lib/number.md)

**Sample**

```js
set.size;
```

## Methods Detailed

### add(value)

The set() method adds or updates an entry in a Set object with a specified key and a value.

**Parameters**

* [Object](/reference/servoycore/dev-api/js-lib/object.md) **value** ;

**Returns:** [Set](/reference/servoycore/dev-api/js-lib/set.md) the Set itself

**Sample**

```js
set.add(value);
```

### clear()

The clear() method removes all elements from a Set object.

**Returns:** void

**Sample**

```js
set.clear();
```

### delete(value)

The delete() method removes the specified element from a Set object by key.

**Parameters**

* [Object](/reference/servoycore/dev-api/js-lib/object.md) **value** ;

**Returns:** [Boolean](/reference/servoycore/dev-api/js-lib/boolean.md) True if the specified element was successfully removed from the Set; false otherwise.

**Sample**

```js
var success = set.delete(key);
```

### entries()

The entries() method returns a new iterator object that contains the \[key, value] pairs for each element in the Set object in insertion order. In this particular case, this iterator object is also an iterable, so the for-of loop can be used..

**Returns:** [Iterator](/reference/servoycore/dev-api/js-lib/iterator.md) the iterator that can be used in for of loops

**Sample**

```js
for(var entry of set.entries()) {}
```

### forEach(callback, thisArgument)

The forEach() method executes a provided function once for each value in the Set object, in insertion order.

**Parameters**

* [Function](/reference/servoycore/dev-api/js-lib/function.md) **callback** ;
* [Object](/reference/servoycore/dev-api/js-lib/object.md) **thisArgument** ;

**Returns:** void

**Sample**

```js
set.forEach(function(keyValuePair) {});
```

### has(key)

The has() method returns a boolean indicating whether an element with the specified value exists in a Set object or not.

**Parameters**

* [Object](/reference/servoycore/dev-api/js-lib/object.md) **key** ;

**Returns:** [Boolean](/reference/servoycore/dev-api/js-lib/boolean.md) True if the Set contains an element with the specified key; false otherwise.

**Sample**

```js
var containsKey = set.has(key);
```

### keys()

The keys() method returns a new iterator object that contains the keys for each element in the Set object in insertion order. In this particular case, this iterator object is also an iterable, so a for...of loop can be used.

**Returns:** [Iterator](/reference/servoycore/dev-api/js-lib/iterator.md) the iterator that can be used in for of loops

**Sample**

```js
var values = set.keys();
```

### values()

The values() method returns a new iterator object that contains the values for each element in the Set object in insertion order.

**Returns:** [Iterator](/reference/servoycore/dev-api/js-lib/iterator.md) the iterator that can be used in for of loops

**Sample**

```js
var values = set.values();
```

***


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