Access to campaign-level extensions.

For example, to access all sitelinks belonging to a campaign:

```
var campaignSitelinkIterator = campaign.extensions().sitelinks().get();
while (campaignSitelinkIterator.hasNext()) {
  var campaignSitelink = campaignSitelinkIterator.next();
}
```

### Methods:

| Member | Type | Description |
|---|---|---|
| [callouts()](https://developers.google.com/google-ads/scripts/docs/reference/adsapp/adsapp_campaignextensions#callouts) | `https://developers.google.com/google-ads/scripts/docs/reference/adsapp/adsapp_campaigncalloutselector` | Returns the selector of all callouts in the campaign. |
| [mobileApps()](https://developers.google.com/google-ads/scripts/docs/reference/adsapp/adsapp_campaignextensions#mobileApps) | `https://developers.google.com/google-ads/scripts/docs/reference/adsapp/adsapp_campaignmobileappselector` | Returns the selector of all mobile apps in the campaign. |
| [phoneNumbers()](https://developers.google.com/google-ads/scripts/docs/reference/adsapp/adsapp_campaignextensions#phoneNumbers) | `https://developers.google.com/google-ads/scripts/docs/reference/adsapp/adsapp_campaignphonenumberselector` | Returns the selector of all phone numbers in the campaign. |
| [prices()](https://developers.google.com/google-ads/scripts/docs/reference/adsapp/adsapp_campaignextensions#prices) | `https://developers.google.com/google-ads/scripts/docs/reference/adsapp/adsapp_campaignpriceselector` | Returns the selector of all prices in the campaign. |
| [sitelinks()](https://developers.google.com/google-ads/scripts/docs/reference/adsapp/adsapp_campaignextensions#sitelinks) | `https://developers.google.com/google-ads/scripts/docs/reference/adsapp/adsapp_campaignsitelinkselector` | Returns the selector of all sitelinks in the campaign. |
| [snippets()](https://developers.google.com/google-ads/scripts/docs/reference/adsapp/adsapp_campaignextensions#snippets) | `https://developers.google.com/google-ads/scripts/docs/reference/adsapp/adsapp_campaignsnippetselector` | Returns the selector of all snippets in the campaign. |

## `callouts()`

Returns the selector of all callouts in the campaign.

### Return values:

| Type | Description |
|---|---|
| `https://developers.google.com/google-ads/scripts/docs/reference/adsapp/adsapp_campaigncalloutselector` | The selector of all callouts in the campaign. |

## `mobileApps()`

Returns the selector of all mobile apps in the campaign.

### Return values:

| Type | Description |
|---|---|
| `https://developers.google.com/google-ads/scripts/docs/reference/adsapp/adsapp_campaignmobileappselector` | The selector of all mobile apps in the campaign. |

## `phoneNumbers()`

Returns the selector of all phone numbers in the campaign.

### Return values:

| Type | Description |
|---|---|
| `https://developers.google.com/google-ads/scripts/docs/reference/adsapp/adsapp_campaignphonenumberselector` | The selector of all phone numbers in the campaign. |

## `prices()`

Returns the selector of all prices in the campaign.

### Return values:

| Type | Description |
|---|---|
| `https://developers.google.com/google-ads/scripts/docs/reference/adsapp/adsapp_campaignpriceselector` | The selector of all prices in the campaign. |

## `sitelinks()`

Returns the selector of all sitelinks in the campaign.

### Return values:

| Type | Description |
|---|---|
| `https://developers.google.com/google-ads/scripts/docs/reference/adsapp/adsapp_campaignsitelinkselector` | The selector of all sitelinks in the campaign. |

## `snippets()`

Returns the selector of all snippets in the campaign.

### Return values:

| Type | Description |
|---|---|
| `https://developers.google.com/google-ads/scripts/docs/reference/adsapp/adsapp_campaignsnippetselector` | The selector of all snippets in the campaign. |