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Jsbool js_definefunction(), Unsigned short *js_valuetostring() – Adobe Extending Flash Professional CS5 User Manual

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EXTENDING FLASH PROFESSIONAL

C-Level Extensibility

Last updated 5/2/2011

typedef JSBool (*JSNative)(JSContext *cx, JSObject *obj, unsigned int argc,
jsval *argv, jsval *rval)

Description
Method; describes C-level implementations of JavaScript functions in the following situations:

The cx pointer is a pointer to an opaque

JSContext

structure, which must be passed to some of the functions in

the JavaScript API. This variable holds the interpreter’s execution context.

The obj pointer is a pointer to the object in whose context the script executes. While the script is running, the

this

keyword is equal to this object.

The argc integer is the number of arguments being passed to the function.

The argv pointer is a pointer to an array of

jsval

structures. The array is

argc

elements in length.

The rval pointer is a pointer to a single

jsval

structure. The function’s return value should be written to

*rval

.

The function returns

JS_TRUE

if successful;

JS_FALSE

otherwise. If the function returns

JS_FALSE

, the current script

stops executing and an error message appears.

JSBool JS_DefineFunction()

Usage

JSBool JS_DefineFunction(unsigned short *name, JSNative call, unsigned int nargs)

Description
Method; registers a C-level function with the JavaScript interpreter in Flash. After the

JS_DefineFunction()

function registers the C-level function that you specify in the call argument, you can invoke it in a JavaScript script by
referring to it with the name that you specify in the name argument. The name argument is case-sensitive.

Typically, this function is called from the

MM_Init()

function, which Flash calls during startup.

Arguments

unsigned short *

name,

JSNative

call,

unsigned int

nargs

The name argument is the name of the function as it is exposed to JavaScript.

The call argument is a pointer to a C-level function. The function must return a

JSBool

, which indicates success or

failure.

The nargs argument is the number of arguments that the function expects to receive.

Returns
A Boolean value:

JS_TRUE

indicates success;

JS_FALSE

indicates failure.

unsigned short *JS_ValueToString()

Usage

unsigned short *JS_ValueToString(JSContext *cx, jsval v, unsigned int *pLength)

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