visual c++ - how to pass c array to javascript from C++ -

i found definition in "wtypes.h"

vt_ptr  = 26, vt_safearray    = 27, vt_carray   = 28, vt_userdefined  = 29, vt_lpstr    = 30, vt_lpwstr   = 31,   *  vt_ptr                 [t]        pointer type *  vt_safearray           [t]        (use vt_array in variant) *  vt_carray              [t]        c style array *  vt_userdefined         [t]        user defined type *  vt_lpstr               [t][p]     null terminated string *  vt_lpwstr              [t][p]     wide null terminated string 

in opinion,this definition show variant can c array,ptr or c point. can't type of arg when use follow code pass c array javascript

stdmethodimp cfilesystemobject::invoke( dispid dispidmember, refiid riid, lcid lcid, word wflags, dispparams *pdispparams, variant *pvarresult, excepinfo *pexcepinfo, uint *puargerr ){     pvarresult->vt = vt_carray|vt_i4;     pvarresult->pintval = new int[4]; } 

how pass c array javascript c++?

there several ways can achieve close goal.

a) have method return safearray (see safearraycreate, safearrayaccessdata et al). can pack variant of type vt_array | vt_i4. javascript cannot consume safearrays directly, can of vbarray object. on javascript side, call this:

  var retarr = new vbarray(yourobject.yourmethod()).toarray() 

note that, if want method callable vbscript in addition javascript, vbscript understands safearrays of variants (vt_array | vt_variant), not of other type. need create safearray of variants, , have each of variants wrap int. javascript work such arrangement, too.

b) implement separate com collection object wrapping array. object expose, say, length , item() properties access individual elements; , optionally _newenum property play vbscript's for each syntax, if that's concern. method create , return instance of object.

i think, though not 100% sure, default property (one dispid of dispid_value) accessible in javascript via objectname[i] syntax, in addition regular objectname.item(i) syntax. if works, make collection object native javascript array.

c) create, populate , return native javascript array object:

http://www.codeproject.com/articles/88753/creating-javascript-arrays-and-other-objects-from

i wouldn't recommend this, ties component intimately particular host. mention completeness.