> For the complete documentation index, see [llms.txt](https://docs.fieldmotion.com/fieldmotion-api-docs/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://docs.fieldmotion.com/fieldmotion-api-docs/invoice/_setform.md).

# \_setForm

Sets a chosen Form to an Invoice.

### Parameters

#### id

The ID of the Invoice being modified

#### val

The ID of the Form to be set to the Invoice

### Example

```
FM_api('Invoice_setForm',[
  'id'=>'697934',
  'val'=>'460477'
  ]
);
```

### Result

#### On Success

Normal result

```
{"ok":1}
```

If the Invoice was already assigned to the chosen Form:

```
{"ok":1,"warning":"no change needed"}
```

#### On Failure

If either the "id" or "val" parameters are not set:

```
{"error":"id and val parameters are both required"}
```

If the value of the "id" parameter does not match an existing Invoice:

<pre><code><strong>{"error":"invoice does not exist"}
</strong></code></pre>

If the value of the "val" parameter does not match an existing Form:

```
{"error":"form does not exist"}
```

If the Invoice being modifed has its Status set as Paid:

```
{"error":"cannot edit invoices that are marked Paid"}
```

If the Form being set to the Invoice an "Invoice Table" type:

```
{"error":"wrong form type"}
```


---

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