---
product: Chilkat
product_version: 11.7.0
language: activex
language_label: ActiveX
class: Js
license: bundle
deprecated: false
reference_html: https://www.chilkatsoft.com/refdoc/xChilkatJsRef.html
---
# Chilkat Js — ActiveX — v11.7.0

> Chilkat 11.7.0 · language=activex · class=Js
> Other versions: replace `11.7.0` in this URL. Other languages: `https://www.chilkatsoft.com/ai-docs/v/11.7.0/<lang>/classes/Js.md`.
> Language-wide rules (install, unlock, error model, strings/bytes): `https://www.chilkatsoft.com/ai-docs/v/11.7.0/activex/guide.md`.

## Purpose

**Execute sandboxed JavaScript inside an application with controlled access to Chilkat features.**

Use `Chilkat.Js` when an application needs to execute JavaScript internally while retaining control over what the script is allowed to access. By default, scripts run in a closed sandbox with the JavaScript language and standard library available, but without filesystem, network, or Chilkat class access unless the host application explicitly enables those capabilities.

**Embedded JavaScript engine**

Run JavaScript code from inside the host application without launching an external scripting process.

**Sandboxed by default**

Start from a restricted execution environment and selectively expose only the capabilities the script should use.

**Enable Chilkat classes**

Allow scripts to use selected Chilkat classes when the host application wants JavaScript to perform controlled Chilkat operations.

**Filesystem restrictions**

Optionally restrict filesystem access so scripts can read or write only within approved locations.

**Script input and output**

Execute JavaScript, pass data through the host-controlled environment, and retrieve results or diagnostics from the script run.

**Controlled automation**

Use JavaScript as an embedded extension language for application-defined workflows while keeping host resources protected.

**Common pattern:** Create a `Js` object, load or provide the JavaScript code, enable only the Chilkat classes and filesystem locations the script is permitted to use, run the script, and inspect the result or diagnostic output. Use `Chilkat.Js` when the application needs scriptability with a security boundary controlled by the host.

For an extended overview, see [Js Class Overview](https://www.chilkatsoft.com/js_class_overview.asp). Also see [About the Chilkat.Js JavaScript Engine](https://www.chilkatsoft.com/chilkat_javascript_engine.asp).

**Third-Party Notice** This software includes portions of the QuickJS JavaScript engine. Copyright © 2017–2024 Fabrice Bellard. Licensed under the MIT License. The Chilkat Js engine was originally derived from QuickJS, but has been extensively modified.

## Object creation, unlocking and error handling

**Object Creation**

```clike
Note:
For a specific major version, use "Chilkat.Js.<major_version>", such as "Chilkat.Js.10" for Chilkat v10.*.*
See Chilkat ActiveX Object Creation

(ASP)
set obj = Server.CreateObject("Chilkat.Js")

(AutoIt)
$obj = ObjCreate("Chilkat.Js")

(Visual Basic 6.0)
Dim obj As New ChilkatJs

(VBScript)
set obj = CreateObject("Chilkat.Js")

(VBA, such as Excel)
Dim obj As New ChilkatJs
See How to Use ActiveX in Excel

(Delphi)
obj := TChilkatJs.Create(Self);

(FoxPro)
loObject = CreateObject('Chilkat.Js')

(Xbase++)
oObject := CreateObject("Chilkat.Js")

(PowerBuilder)
lole_object = create oleobject
li_rc = lole_object.ConnectToNewObject("Chilkat.Js")

(SQL Server)
EXEC @hr = sp_OACreate 'Chilkat.Js', @obj OUT

(Javascript)
var obj = new ActiveXObject("Chilkat.Js");
```

Call `Global.UnlockBundle` once at the start of the program, before using this or any other Chilkat class. Any string unlocks a fully functional 30-day trial; a purchased unlock code is used in production. See `guide.md` for the exact code in ActiveX.

How failure is reported depends on the method's return type and is stated in the note under each method below. In every case the diagnostic text is in the `LastErrorText` property of the object whose method was called.

## Members common to every Chilkat class

Documented once per language in `common-members.md`; listed here so this page is self-contained.

| Property | Signature | Access | Meaning |
|---|---|---|---|
| `DebugLogFilePath` | `DebugLogFilePath As String` | read/write | If set to a file path, this property logs the LastErrorText of each Chilkat method or property call to the specified file. |
| `LastBinaryResult` | `LastBinaryResult As Variant (read-only)` | read-only | This property is mainly used in SQL Server stored procedures to retrieve binary data from the last method call that returned binary data. |
| `LastErrorHtml` | `LastErrorHtml As String (read-only)` | read-only | Provides HTML-formatted information about the last called method or property. |
| `LastErrorText` | `LastErrorText As String (read-only)` | read-only | Provides plain text information about the last called method or property. |
| `LastErrorXml` | `LastErrorXml As String (read-only)` | read-only | Provides XML-formatted information about the last called method or property. |
| `LastMethodSuccess` | `LastMethodSuccess As Long` | read/write | Indicates the success or failure of the most recent method call: `1` means success, `0` means failure. |
| `LastStringResult` | `LastStringResult As String (read-only)` | read-only | In SQL Server stored procedures, this property holds the string return value of the most recent method call that returns a string. |
| `LastStringResultLen` | `LastStringResultLen As Long (read-only)` | read-only | The length, in characters, of the string contained in the LastStringResult property. |
| `VerboseLogging` | `VerboseLogging As Long` | read/write | If set to `1`, then the contents of LastErrorText (or LastErrorXml, or LastErrorHtml) may contain more verbose information. |
| `Version` | `Version As String (read-only)` | read-only | Version of the component/library, such as "10.1.0" |

## Member index

| Member | Kind | Signature |
|---|---|---|
| `TimeoutSeconds` | property, read/write | `TimeoutSeconds As Long` |
| `CallFunction` | method | `CallFunction(funcJson As ChilkatJsonObject, resultJson As ChilkatJsonObject) As Long` |
| `ConsoleOutputSb` | method | `ConsoleOutputSb(sb As ChilkatStringBuilder)` |
| `Eval` | method | `Eval(jscript As ChilkatStringBuilder, resultJson As ChilkatJsonObject) As Long` |
| `SetCkPermission` | method | `SetCkPermission(chilkatClassName As String, permission As String) As Long` |

## Properties

### Js.TimeoutSeconds

`Chilkat 11.7.0 · activex · Js · TimeoutSeconds · property · read/write · since 11.4.0`

```
TimeoutSeconds As Long
```

Specify a timeout in seconds to prevent JavaScript from running indefinitely, such as in an infinite loop. By default, the value is 0, meaning no timeout is set and infinite loops will continue forever.

## Methods

### Js.CallFunction

`Chilkat 11.7.0 · activex · Js · CallFunction · method · since 11.4.0`

```
CallFunction(funcJson As ChilkatJsonObject, resultJson As ChilkatJsonObject) As Long
```

Calls a JavaScript function. The function name and arguments are passed in `funcJson`. The result is returned in `resultJson`.

Returns 1 for success, 0 for failure.

Async variant: `CallFunctionAsync` — same arguments, returns a `Task` (see Async variants below).

### Js.ConsoleOutputSb

`Chilkat 11.7.0 · activex · Js · ConsoleOutputSb · method · since 11.4.0`

```
ConsoleOutputSb(sb As ChilkatStringBuilder)
```

Returns the console output in `sb` from the last call to `Eval` .

### Js.Eval

`Chilkat 11.7.0 · activex · Js · Eval · method · since 11.4.0`

```
Eval(jscript As ChilkatStringBuilder, resultJson As ChilkatJsonObject) As Long
```

Run `jscript` as a script. Return output and errors in `resultJson`.

Returns 1 for success, 0 for failure.

Async variant: `EvalAsync` — same arguments, returns a `Task` (see Async variants below).

### Js.SetCkPermission

`Chilkat 11.7.0 · activex · Js · SetCkPermission · method · since 11.4.0`

```
SetCkPermission(chilkatClassName As String, permission As String) As Long
```

Sets sandbox related permissions for Chilkat objects. The `chilkatClassName` is the name of the Chilkat class (case-insensitive), such as `Http`, `Rest`, `"MailMan"`, `"Ftp2"`, `"Ssh"`, etc. The `chilkatClassName` can also be set to `"all"` to apply the permission to all Chilkat classes.

Possible values for `permission` are:

- `disable` - Your JavaScript code is not allowed to create an instance of the Chilkat class. A JavaScript exception is thrown when trying to create a Chilkat object of a class that is disabled.
- `sandbox` - Objects for the Chilkat class can be instantiated in JavaScript, but they have no read or write access to the local filesystem.
- `readOnly` - Objects for the Chilkat class can be instantiated in JavaScript and have read-only access to the local filesystem.
- `writeOnly` - Objects for the Chilkat class can be instantiated in JavaScript and have write-only access to the local filesystem.
- `readWrite` - Objects for the Chilkat class can be instantiated in JavaScript and have read/write access to the local filesystem.

By default, all Chilkat classes are **disabled**. Your application must enable `"all"` or specific Chilkat classes before calling `Eval` or `CallFunction` .

Returns 1 for success, 0 for failure.

## Events and callbacks

### Js.TaskCompleted (event)

`Chilkat 11.7.0 · activex · Js · TaskCompleted · event`

```
TaskCompleted(task As ChilkatTask)
```

Called from the background thread when an asynchronous task completes.

**VB6 Event callback implementation:**

**Important:** Event callbacks from ***asynchronous method calls*** are generally not possible from the ActiveX. See [VB6 Event Callbacks](https://www.chilkatsoft.com/vb6_event_callbacks.asp)

```vb
Dim WithEvents myJs As ChilkatJs

Private Sub myJs_TaskCompleted(task As ChilkatTask)

	'Insert application code here.

End Sub
```

## Async variants

Each returns a `Task` instead of the result and takes the same arguments as the synchronous method; run the task, wait for `Finished`, then read the result from the task. No new Async methods are added from 11.7.0 on.

```
CallFunctionAsync(funcJson As ChilkatJsonObject, resultJson As ChilkatJsonObject) As ChilkatTask
EvalAsync(jscript As ChilkatStringBuilder, resultJson As ChilkatJsonObject) As ChilkatTask
```

## Related classes

[`JsonObject`](https://www.chilkatsoft.com/ai-docs/v/11.7.0/activex/classes/JsonObject.md), [`StringBuilder`](https://www.chilkatsoft.com/ai-docs/v/11.7.0/activex/classes/StringBuilder.md)