Js Classic ASP Reference Documentation

Js

Current Version: 11.6.0

Chilkat.Js

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.
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

set js = Server.CreateObject("Chilkat.Js")

' ... use js ...

set js = Nothing

Classic ASP creates Chilkat objects with Server.CreateObject. The registered Chilkat ActiveX must match the bitness of the IIS application pool: a pool with Enable 32-Bit Applications set to True needs the 32-bit ActiveX, otherwise the 64-bit ActiveX. To bind to a specific major version of Chilkat, append the major version number to the ProgID, such as Server.CreateObject("Chilkat.Js.11") for Chilkat v11.*.*.

VBScript requires set when assigning an object, so the signatures on this page show set x = obj.Method(...) for methods that return a Chilkat object; test the result with Is Nothing, since a method that fails to return an object returns Nothing. A method with no return value is called as a statement without parentheses (obj.Method arg1, arg2). Boolean properties, arguments and return values are integers in the ActiveX: pass 1 or 0, and test success with = 1. Byte arrays are Variant arrays and can be sent with Response.BinaryWrite. Asynchronous (*Async) methods and event callbacks are not used from Classic ASP.

Properties

DebugLogFilePath
js.DebugLogFilePath ' String

If set to a file path, this property logs the LastErrorText of each Chilkat method or property call to the specified file. This logging helps identify the context and history of Chilkat calls leading up to any crash or hang, aiding in debugging.

Enabling the VerboseLogging property provides more detailed information. This property is mainly used for debugging rare instances where a Chilkat method call causes a hang or crash, which should generally not happen.

Possible causes of hangs include:

  • A timeout property set to 0, indicating an infinite timeout.
  • A hang occurring within an event callback in the application code.
  • An internal bug in the Chilkat code causing the hang.

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LastBinaryResult
js.LastBinaryResult ' Variant (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. It is only accessible if Chilkat.Global.KeepBinaryResult is set to 1. This feature allows for the retrieval of large varbinary results in an SQL Server environment, which has restrictions on returning large data via method calls, though temp tables can handle binary properties.

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LastErrorHtml
js.LastErrorHtml ' String (read-only)

Provides HTML-formatted information about the last called method or property. If a method call fails or behaves unexpectedly, check this property for details. Note that information is available regardless of the method call's success.

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LastErrorText
js.LastErrorText ' String (read-only)

Provides plain text information about the last called method or property. If a method call fails or behaves unexpectedly, check this property for details. Note that information is available regardless of the method call's success.

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LastErrorXml
js.LastErrorXml ' String (read-only)

Provides XML-formatted information about the last called method or property. If a method call fails or behaves unexpectedly, check this property for details. Note that information is available regardless of the method call's success.

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LastMethodSuccess
js.LastMethodSuccess ' Long

Indicates the success or failure of the most recent method call: 1 means success, 0 means failure. This property remains unchanged by property setters or getters. This method is present to address challenges in checking for null or Nothing returns in certain programming languages. Note: This property does not apply to methods that return integer values or to boolean-returning methods where the boolean does not indicate success or failure.

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LastStringResult
js.LastStringResult ' String (read-only)

In SQL Server stored procedures, this property holds the string return value of the most recent method call that returns a string. It is accessible only when Chilkat.Global.KeepStringResult is set to TRUE. SQL Server has limitations on string lengths returned from methods and properties, but temp tables can be used to access large strings.

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LastStringResultLen
js.LastStringResultLen ' Long (read-only)

The length, in characters, of the string contained in the LastStringResult property.

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TimeoutSeconds
js.TimeoutSeconds ' Long
Introduced in version 11.4.0

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.

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VerboseLogging
js.VerboseLogging ' Long

If set to 1, then the contents of LastErrorText (or LastErrorXml, or LastErrorHtml) may contain more verbose information. The default value is 0. Verbose logging should only be used for debugging. The potentially large quantity of logged information may adversely affect peformance.

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Version
js.Version ' String (read-only)

Version of the component/library, such as "10.1.0"

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Methods

CallFunction
success = js.CallFunction(funcJson, resultJson) ' Long (1/0)
Introduced in version 11.4.0

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.

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ConsoleOutputSb
js.ConsoleOutputSb sb
Introduced in version 11.4.0

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

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Eval
success = js.Eval(jscript, resultJson) ' Long (1/0)
Introduced in version 11.4.0

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

Returns 1 for success, 0 for failure.

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SetCkPermission
success = js.SetCkPermission(chilkatClassName, permission) ' Long (1/0)
Introduced in version 11.4.0

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.

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