Lingo Dictionary > D-F > on EvalScript |  |

on EvalScript

Syntax

    on EvalScript aParam
    	statement(s)
    end

Description

System message and event handler; in a Shockwave movie, contains statements that run when the handler receives an `EvalScript` message from a browser. The parameter is a string passed in from the browser.

| The `EvalScript` message can include a string that Director can interpret as a Lingo statement. Lingo cannot accept nested strings. If the handler you are calling expects a string as a parameter, pass the parameter as a symbol.
| The `on EvalScript` handler is called by the `EvalScript()` scripting method from JavaScript or VBScript in a browser.
| The Director player for Java doesn't support the `on EvalScript` handler. To enable communication between an applet and a browser, use Java, JavaScript, or VBScript.

Include only those behaviors in `on EvalScript` that you want users to control; for security reasons, don't give complete access to behaviors.

Note: If you place a return at the end of your EvalScript handler, the value returned can be used by JavaScript in the browser.

Example

This shows how to make the playback head jump to a specific frame depending on what frame is passed in as the parameter:

    on EvalScript aParam
    	go frame aParam
    end

Example

This handler runs the statement `go frame aParam` if it receives an `EvalScript` message that includes dog, cat, or tree as an argument:

    on EvalScript aParam
    	case aParam of
    		"dog", "cat", "tree": go frame aParam
    	end case
    end

A possible calling statement for this in JavaScript would be `EvalScript ("dog")`.

Example

This handler takes an argument that can be a number or symbol:

    on EvalScript aParam
    	if word 1 of aParam = "myHandler" then
    		do aParam
    	end if
    end

Example

This handler normally requires a string as its argument. The argument is received as a symbol and then converted to a string within the handler by the `string` function:

    on myHandler aParam
    	go to frame string(aParam)
    end

See also

`externalEvent`,`return (keyword)`