Fetches ad params. Unlike other selectors, does not support filtering or sorting.

Typical usage:

```
var adParamSelector = AdsApp.adParams();

var adParamIterator = adParamSelector.get();
while (adParamIterator.hasNext()) {
  var adParam = adParamIterator.next();
}
```
Related:

- [AdParamIterator](https://developers.google.com/google-ads/scripts/docs/reference/adsapp/adsapp_adparamiterator)
- [AdParam](https://developers.google.com/google-ads/scripts/docs/reference/adsapp/adsapp_adparam)

### Methods:

| Member | Type | Description |
|---|---|---|
| [get()](https://developers.google.com/google-ads/scripts/docs/reference/adsapp/adsapp_adparamselector#get) | `https://developers.google.com/google-ads/scripts/docs/reference/adsapp/adsapp_adparamiterator` | Fetches the requested ad params and returns an iterator. |
| [orderBy(orderBy)](https://developers.google.com/google-ads/scripts/docs/reference/adsapp/adsapp_adparamselector#orderBy_orderBy) | `https://developers.google.com/google-ads/scripts/docs/reference/adsapp/adsapp_adparamselector` | Specifies the ordering of the resulting entities. |
| [withCondition(condition)](https://developers.google.com/google-ads/scripts/docs/reference/adsapp/adsapp_adparamselector#withCondition_condition) | `https://developers.google.com/google-ads/scripts/docs/reference/adsapp/adsapp_adparamselector` | Adds the specified condition to the selector in order to narrow down the results. |
| [withLimit(limit)](https://developers.google.com/google-ads/scripts/docs/reference/adsapp/adsapp_adparamselector#withLimit_limit) | `https://developers.google.com/google-ads/scripts/docs/reference/adsapp/adsapp_adparamselector` | Specifies limit for the selector to use. |

## `get()`

Fetches the requested ad params and returns an iterator.

### Return values:

| Type | Description |
|---|---|
| `https://developers.google.com/google-ads/scripts/docs/reference/adsapp/adsapp_adparamiterator` | Iterator of the requested ad params. |

## `orderBy(orderBy)`

Specifies the ordering of the resulting entities. The `orderBy` parameter can have one of the following forms:

- `orderBy("ad_parameter.parameter_index")` - orders results by index, in ascending order.
- `orderBy("ad_parameter.parameter_index ASC")` - orders results by index, in ascending order.
- `orderBy("ad_parameter.insertion_text DESC")` - orders results by insertion text, in descending order.

### Arguments:

| Name | Type | Description |
|---|---|---|
| orderBy | `String` | Ordering to apply. |

### Return values:

| Type | Description |
|---|---|
| `https://developers.google.com/google-ads/scripts/docs/reference/adsapp/adsapp_adparamselector` | The selector with ordering applied. |

## `withCondition(condition)`

Adds the specified condition to the selector in order to narrow down the results.

Multiple conditions can be added to the same selector:

```
selector = selector
    .withCondition("ad_parameter.parameter_index = 1")
    .withCondition("ad_parameter.insertion_text = '$99'");
```
All specified conditions are `AND`-ed together. The above example will retrieve ad params whose index is 1 and insertion text is '$99'.

The condition passed into this method must be of the following form:

```
"COLUMN_NAME OPERATOR VALUE"
```

### Arguments:

| Name | Type | Description |
|---|---|---|
| condition | `String` | Condition to add to the selector. |

### Return values:

| Type | Description |
|---|---|
| `https://developers.google.com/google-ads/scripts/docs/reference/adsapp/adsapp_adparamselector` | The selector with the condition applied. |

## `withLimit(limit)`

Specifies limit for the selector to use. For instance, `withLimit(50)` returns only the first 50 entities.

### Arguments:

| Name | Type | Description |
|---|---|---|
| limit | `int` | How many entities to return. |

### Return values:

| Type | Description |
|---|---|
| `https://developers.google.com/google-ads/scripts/docs/reference/adsapp/adsapp_adparamselector` | The selector with limit applied. |