Aspose::Words::Fields::FieldCollection class

FieldCollection class

A collection of Field objects that represents the fields in the specified range. To learn more, visit the Working with Fields documentation article.

class FieldCollection : public System::Collections::Generic::IEnumerable<System::SharedPtr<Aspose::Words::Fields::Field>>

Methods

Method	Description
Clear()	Removes all fields of this collection from the document and from this collection itself.
get_Count()	Returns the number of the fields in the collection.
GetEnumerator() override	Returns an enumerator object.
GetType() const override
idx_get(int32_t)	Returns a field at the specified index.
Is(const System::TypeInfo&) const override
Remove(const System::SharedPtr<Aspose::Words::Fields::Field>&)	Removes the specified field from this collection and from the document.
RemoveAt(int32_t)	Removes a field at the specified index from this collection and from the document.
static Type()

Remarks

An instance of this collection iterates fields which start fall within the specified range.

The FieldCollection collection does not own the fields it contains, rather, is just a selection of fields.

The FieldCollection collection is “live”, i.e. changes to the children of the node object that it was created from are immediately reflected in the fields returned by the FieldCollection properties and methods.

Examples

Shows how to work with a collection of fields.

void FieldCollection_()
{
    auto doc = MakeObject<Document>();
    auto builder = MakeObject<DocumentBuilder>(doc);

    builder->InsertField(u" DATE \\@ \"dddd, d MMMM yyyy\" ");
    builder->InsertField(u" TIME ");
    builder->InsertField(u" REVNUM ");
    builder->InsertField(u" AUTHOR  \"John Doe\" ");
    builder->InsertField(u" SUBJECT \"My Subject\" ");
    builder->InsertField(u" QUOTE \"Hello world!\" ");
    doc->UpdateFields();

    SharedPtr<FieldCollection> fields = doc->get_Range()->get_Fields();

    ASSERT_EQ(6, fields->get_Count());

    // Iterate over the field collection, and print contents and type
    // of every field using a custom visitor implementation.
    auto fieldVisitor = MakeObject<ExField::FieldVisitor>();

    {
        SharedPtr<System::Collections::Generic::IEnumerator<SharedPtr<Field>>> fieldEnumerator = fields->GetEnumerator();
        while (fieldEnumerator->MoveNext())
        {
            if (fieldEnumerator->get_Current() != nullptr)
            {
                fieldEnumerator->get_Current()->get_Start()->Accept(fieldVisitor);
                if (fieldEnumerator->get_Current()->get_Separator() != nullptr)
                {
                    fieldEnumerator->get_Current()->get_Separator()->Accept(fieldVisitor);
                }
                fieldEnumerator->get_Current()->get_End()->Accept(fieldVisitor);
            }
            else
            {
                std::cout << "There are no fields in the document." << std::endl;
            }
        }
    }

    std::cout << fieldVisitor->GetText() << std::endl;
}

class FieldVisitor : public DocumentVisitor
{
public:
    FieldVisitor()
    {
        mBuilder = MakeObject<System::Text::StringBuilder>();
    }

    String GetText()
    {
        return mBuilder->ToString();
    }

    VisitorAction VisitFieldStart(SharedPtr<FieldStart> fieldStart) override
    {
        mBuilder->AppendLine(String(u"Found field: ") + System::ObjectExt::ToString(fieldStart->get_FieldType()));
        mBuilder->AppendLine(String(u"\tField code: ") + fieldStart->GetField()->GetFieldCode());
        mBuilder->AppendLine(String(u"\tDisplayed as: ") + fieldStart->GetField()->get_Result());

        return VisitorAction::Continue;
    }

    VisitorAction VisitFieldSeparator(SharedPtr<FieldSeparator> fieldSeparator) override
    {
        mBuilder->AppendLine(String(u"\tFound separator: ") + fieldSeparator->GetText());

        return VisitorAction::Continue;
    }

    VisitorAction VisitFieldEnd(SharedPtr<FieldEnd> fieldEnd) override
    {
        mBuilder->AppendLine(String(u"End of field: ") + System::ObjectExt::ToString(fieldEnd->get_FieldType()));

        return VisitorAction::Continue;
    }

private:
    SharedPtr<System::Text::StringBuilder> mBuilder;
};

Shows how to remove fields from a field collection.

auto doc = MakeObject<Document>();
auto builder = MakeObject<DocumentBuilder>(doc);

builder->InsertField(u" DATE \\@ \"dddd, d MMMM yyyy\" ");
builder->InsertField(u" TIME ");
builder->InsertField(u" REVNUM ");
builder->InsertField(u" AUTHOR  \"John Doe\" ");
builder->InsertField(u" SUBJECT \"My Subject\" ");
builder->InsertField(u" QUOTE \"Hello world!\" ");
doc->UpdateFields();

SharedPtr<FieldCollection> fields = doc->get_Range()->get_Fields();

ASSERT_EQ(6, fields->get_Count());

// Below are four ways of removing fields from a field collection.
// 1 -  Get a field to remove itself:
fields->idx_get(0)->Remove();
ASSERT_EQ(5, fields->get_Count());

// 2 -  Get the collection to remove a field that we pass to its removal method:
SharedPtr<Field> lastField = fields->idx_get(3);
fields->Remove(lastField);
ASSERT_EQ(4, fields->get_Count());

// 3 -  Remove a field from a collection at an index:
fields->RemoveAt(2);
ASSERT_EQ(3, fields->get_Count());

// 4 -  Remove all the fields from the collection at once:
fields->Clear();
ASSERT_EQ(0, fields->get_Count());

See Also

• Namespace Aspose::Words::Fields
• Library Aspose.Words for C++