class WIN32OLE::Variant

WIN32OLE::Variant objects represents OLE variant.

Win32OLE converts Ruby object into OLE variant automatically when invoking OLE methods. If OLE method requires the argument which is different from the variant by automatic conversion of Win32OLE, you can convert the specified variant type by using WIN32OLE::Variant class.

param = WIN32OLE::Variant.new(10, WIN32OLE::VARIANT::VT_R4)
oleobj.method(param)

WIN32OLE::Variant does not support VT_RECORD variant. Use WIN32OLE::Record class instead of WIN32OLE::Variant if the VT_RECORD variant is needed.

Constants

Empty

represents VT_EMPTY OLE object.

NoParam

represents VT_ERROR variant with DISP_E_PARAMNOTFOUND. This constants is used for not specified parameter.

fso = WIN32OLE.new("Scripting.FileSystemObject")
fso.openTextFile(filename, WIN32OLE::Variant::NoParam, false)

Nothing

represents Nothing of VB.NET or VB.

Null

represents VT_NULL OLE object.

Public Class Methods

array(ary, vt) click to toggle source

Returns Ruby object wrapping OLE variant whose variant type is VT_ARRAY. The first argument should be Array object which specifies dimensions and each size of dimensions of OLE array. The second argument specifies variant type of the element of OLE array.

The following create 2 dimensions OLE array. The first dimensions size is 3, and the second is 4.

ole_ary = WIN32OLE::Variant.array([3,4], VT_I4)
ruby_ary = ole_ary.value # => [[0, 0, 0, 0], [0, 0, 0, 0], [0, 0, 0, 0]]

static VALUE
folevariant_s_array(VALUE klass, VALUE elems, VALUE vvt)
{
    VALUE obj = Qnil;
    VARTYPE vt;
    struct olevariantdata *pvar;
    SAFEARRAYBOUND *psab = NULL;
    SAFEARRAY *psa = NULL;
    UINT dim = 0;
    UINT i = 0;

    ole_initialize();

    vt = RB_NUM2UINT(vvt);
    vt = (vt | VT_ARRAY);
    Check_Type(elems, T_ARRAY);
    obj = folevariant_s_allocate(klass);

    TypedData_Get_Struct(obj, struct olevariantdata, &olevariant_datatype, pvar);
    dim = RARRAY_LEN(elems);

    psab = ALLOC_N(SAFEARRAYBOUND, dim);

    if(!psab) {
        rb_raise(rb_eRuntimeError, "memory allocation error");
    }

    for (i = 0; i < dim; i++) {
        psab[i].cElements = RB_FIX2INT(rb_ary_entry(elems, i));
        psab[i].lLbound = 0;
    }

    psa = SafeArrayCreate((VARTYPE)(vt & VT_TYPEMASK), dim, psab);
    if (psa == NULL) {
        if (psab) free(psab);
        rb_raise(rb_eRuntimeError, "memory allocation error(SafeArrayCreate)");
    }

    V_VT(&(pvar->var)) = vt;
    if (vt & VT_BYREF) {
        V_VT(&(pvar->realvar)) = (vt & ~VT_BYREF);
        V_ARRAY(&(pvar->realvar)) = psa;
        V_ARRAYREF(&(pvar->var)) = &(V_ARRAY(&(pvar->realvar)));
    } else {
        V_ARRAY(&(pvar->var)) = psa;
    }
    if (psab) free(psab);
    return obj;
}

new(val, vartype) #→ WIN32OLE::Variant object. click to toggle source

Returns Ruby object wrapping OLE variant. The first argument specifies Ruby object to convert OLE variant variable. The second argument specifies VARIANT type. In some situation, you need the WIN32OLE::Variant object to pass OLE method

shell = WIN32OLE.new("Shell.Application")
folder = shell.NameSpace("C:\\Windows")
item = folder.ParseName("tmp.txt")
# You can't use Ruby String object to call FolderItem.InvokeVerb.
# Instead, you have to use WIN32OLE::Variant object to call the method.
shortcut = WIN32OLE::Variant.new("Create Shortcut(\&S)")
item.invokeVerb(shortcut)

static VALUE
folevariant_initialize(VALUE self, VALUE args)
{
    int len = 0;
    VARIANT var;
    VALUE val;
    VALUE vvt;
    VARTYPE vt;
    struct olevariantdata *pvar;

    len = RARRAY_LEN(args);
    rb_check_arity(len, 1, 3);
    VariantInit(&var);
    val = rb_ary_entry(args, 0);

    check_type_val2variant(val);

    TypedData_Get_Struct(self, struct olevariantdata, &olevariant_datatype, pvar);
    if (len == 1) {
        ole_val2variant(val, &(pvar->var));
    } else {
        vvt = rb_ary_entry(args, 1);
        vt = RB_NUM2INT(vvt);
        if ((vt & VT_TYPEMASK) == VT_RECORD) {
            rb_raise(rb_eArgError, "not supported VT_RECORD WIN32OLE::Variant object");
        }
        ole_val2olevariantdata(val, vt, pvar);
    }
    return self;
}

Public Instance Methods

variant[i,j,...] #→ element of OLE array. click to toggle source

Returns the element of WIN32OLE::Variant object(OLE array). This method is available only when the variant type of WIN32OLE::Variant object is VT_ARRAY.

REMARK:

The all indices should be 0 or natural number and
lower than or equal to max indices.
(This point is different with Ruby Array indices.)

obj = WIN32OLE::Variant.new([[1,2,3],[4,5,6]])
p obj[0,0] # => 1
p obj[1,0] # => 4
p obj[2,0] # => WIN32OLE::RuntimeError
p obj[0, -1] # => WIN32OLE::RuntimeError

static VALUE
folevariant_ary_aref(int argc, VALUE *argv, VALUE self)
{
    struct olevariantdata *pvar;
    SAFEARRAY *psa;
    VALUE val = Qnil;
    VARIANT variant;
    LONG *pid;
    HRESULT hr;

    TypedData_Get_Struct(self, struct olevariantdata, &olevariant_datatype, pvar);
    if (!V_ISARRAY(&(pvar->var))) {
        rb_raise(eWIN32OLERuntimeError,
                 "`[]' is not available for this variant type object");
    }
    psa = get_locked_safe_array(self);
    if (psa == NULL) {
        return val;
    }

    pid = ary2safe_array_index(argc, argv, psa);

    VariantInit(&variant);
    V_VT(&variant) = (V_VT(&(pvar->var)) & ~VT_ARRAY) | VT_BYREF;
    hr = SafeArrayPtrOfIndex(psa, pid, &V_BYREF(&variant));
    if (FAILED(hr)) {
        ole_raise(hr, eWIN32OLERuntimeError, "failed to SafeArrayPtrOfIndex");
    }
    val = ole_variant2val(&variant);

    unlock_safe_array(psa);
    if (pid) free(pid);
    return val;
}

variant[i,j,...] = val #→ set the element of OLE array click to toggle source

Set the element of WIN32OLE::Variant object(OLE array) to val. This method is available only when the variant type of WIN32OLE::Variant object is VT_ARRAY.

REMARK:

The all indices should be 0 or natural number and
lower than or equal to max indices.
(This point is different with Ruby Array indices.)

obj = WIN32OLE::Variant.new([[1,2,3],[4,5,6]])
obj[0,0] = 7
obj[1,0] = 8
p obj.value # => [[7,2,3], [8,5,6]]
obj[2,0] = 9 # => WIN32OLE::RuntimeError
obj[0, -1] = 9 # => WIN32OLE::RuntimeError

static VALUE
folevariant_ary_aset(int argc, VALUE *argv, VALUE self)
{
    struct olevariantdata *pvar;
    SAFEARRAY *psa;
    VARIANT var;
    VARTYPE vt;
    LONG *pid;
    HRESULT hr;
    VOID *p = NULL;

    TypedData_Get_Struct(self, struct olevariantdata, &olevariant_datatype, pvar);
    if (!V_ISARRAY(&(pvar->var))) {
        rb_raise(eWIN32OLERuntimeError,
                 "`[]' is not available for this variant type object");
    }
    psa = get_locked_safe_array(self);
    if (psa == NULL) {
        rb_raise(rb_eRuntimeError, "failed to get SafeArray pointer");
    }

    pid = ary2safe_array_index(argc-1, argv, psa);

    VariantInit(&var);
    vt = (V_VT(&(pvar->var)) & ~VT_ARRAY);
    p = val2variant_ptr(argv[argc-1], &var, vt);
    if ((V_VT(&var) == VT_DISPATCH && V_DISPATCH(&var) == NULL) ||
        (V_VT(&var) == VT_UNKNOWN && V_UNKNOWN(&var) == NULL)) {
        rb_raise(eWIN32OLERuntimeError, "argument does not have IDispatch or IUnknown Interface");
    }
    hr = SafeArrayPutElement(psa, pid, p);
    if (FAILED(hr)) {
        ole_raise(hr, eWIN32OLERuntimeError, "failed to SafeArrayPutElement");
    }

    unlock_safe_array(psa);
    if (pid) free(pid);
    return argv[argc-1];
}

value #→ Ruby object. click to toggle source

Returns Ruby object value from OLE variant.

obj = WIN32OLE::Variant.new(1, WIN32OLE::VARIANT::VT_BSTR)
obj.value # => "1" (not Integer object, but String object "1")

static VALUE
folevariant_value(VALUE self)
{
    struct olevariantdata *pvar;
    VALUE val = Qnil;
    VARTYPE vt;
    int dim;
    SAFEARRAY *psa;
    TypedData_Get_Struct(self, struct olevariantdata, &olevariant_datatype, pvar);

    val = ole_variant2val(&(pvar->var));
    vt = V_VT(&(pvar->var));

    if ((vt & ~VT_BYREF) == (VT_UI1|VT_ARRAY)) {
        if (vt & VT_BYREF) {
            psa = *V_ARRAYREF(&(pvar->var));
        } else {
            psa  = V_ARRAY(&(pvar->var));
        }
        if (!psa) {
            return val;
        }
        dim = SafeArrayGetDim(psa);
        if (dim == 1) {
            val = rb_funcall(val, rb_intern("pack"), 1, rb_str_new2("C*"));
        }
    }
    return val;
}

value = val #→ set WIN32OLE::Variant value to val. click to toggle source

Sets variant value to val. If the val type does not match variant value type(vartype), then val is changed to match variant value type(vartype) before setting val. This method is not available when vartype is VT_ARRAY(except VT_UI1|VT_ARRAY). If the vartype is VT_UI1|VT_ARRAY, the val should be String object.

obj = WIN32OLE::Variant.new(1) # obj.vartype is WIN32OLE::VARIANT::VT_I4
obj.value = 3.2 # 3.2 is changed to 3 when setting value.
p obj.value # => 3

static VALUE
folevariant_set_value(VALUE self, VALUE val)
{
    struct olevariantdata *pvar;
    VARTYPE vt;
    TypedData_Get_Struct(self, struct olevariantdata, &olevariant_datatype, pvar);
    vt = V_VT(&(pvar->var));
    if (V_ISARRAY(&(pvar->var)) && ((vt & ~VT_BYREF) != (VT_UI1|VT_ARRAY) || !RB_TYPE_P(val, T_STRING))) {
        rb_raise(eWIN32OLERuntimeError,
                 "`value=' is not available for this variant type object");
    }
    ole_val2olevariantdata(val, vt, pvar);
    return Qnil;
}

vartype #→ OLE variant type. click to toggle source

Returns OLE variant type.

obj = WIN32OLE::Variant.new("string")
obj.vartype # => WIN32OLE::VARIANT::VT_BSTR

static VALUE
folevariant_vartype(VALUE self)
{
    struct olevariantdata *pvar;
    TypedData_Get_Struct(self, struct olevariantdata, &olevariant_datatype, pvar);
    return RB_INT2FIX(V_VT(&pvar->var));
}