# Javascript: ApplicationField.setParameters Method

> Sets the field's parameters.

- **Product:** DS Server
- **Section:** Reference
- **Kind:** Method
- **Introduced:** 28.0
- **Path:** DS Server > Reference > JavaScript API > Javascript: ApplicationField.setParameters Method
- **492 words**
- **Web URL:** https://docs.textcontrol.com/ds-server/reference/javascript/applicationfield/setparameters-method/
- **LLMs URL:** https://docs.textcontrol.com/ds-server/reference/javascript/applicationfield/setparameters-method/llms.txt
- **LLMs-Full URL:** https://docs.textcontrol.com/ds-server/reference/javascript/applicationfield/setparameters-method/llms-full.txt

---

### Description

Sets the field's parameters.

### Syntax

```javascript
<void> ApplicationField.setParameters(<string[]> parameters, [<EmptyRequestCallback> callback], [<ErrorCallback> errorCallback])
```

### Parameters

| Parameter | Description |
|---|---|
| parameters | The parameters. |
| callback | Optional. Is called when the operation completed. |
| errorCallback | Optional. Is called when the operation failed with an error. |

### Examples

The following example changes the current application field into an invoice-number merge field while keeping its definition consistent.

```javascript
function onTxError(error) {
    console.error("TX Text Control error:", error.msg);
    error.handled = true;
}

TXTextControl.textParts.getMainText(function(mainText) {
    mainText.applicationFields.getItem(function(applicationField) {
        if (!applicationField) {
            console.warn("Place the input position in an application field.");
            return;
        }

        applicationField.setTypeName("MERGEFIELD", function() {
            applicationField.setParameters(
                ["InvoiceNumber", "\\* MERGEFORMAT"],
                function() {
                    console.log("The merge field now targets InvoiceNumber.");
                },
                onTxError
            );
        }, onTxError);
    }, onTxError);
}, onTxError);
```

---

## Nearby

- **Previous:** [Javascript: ApplicationField.setFormat Method](https://docs.textcontrol.com/ds-server/reference/javascript/applicationfield/setformat-method/llms-full.txt)
- **Next:** [Javascript: ApplicationField.setTypeName Method](https://docs.textcontrol.com/ds-server/reference/javascript/applicationfield/settypename-method/llms-full.txt)