Aspose::Words::MailMerging::IMailMergeDataSource interface

IMailMergeDataSource interface

Implement this interface to allow mail merge from a custom data source, such as a list of objects. Master-detail data is also supported.

class IMailMergeDataSource : public virtual System::Object

Methods

Method	Description
virtual get_TableName()	Returns the name of the data source.
virtual GetChildDataSource(System::String)	The Aspose.Words mail merge engine invokes this method when it encounters a beginning of a nested mail merge region.
GetType() const override
virtual GetValue(System::String, System::SharedPtr<System::Object>&)
Is(const System::TypeInfo&) const override
virtual MoveNext()	Advances to the next record in the data source.
static Type()

Remarks

When a data source is created, it should be initialized to point to BOF (before the first record). The Aspose.Words mail merge engine will invoke MoveNext to advance to next record and then invoke GetValue() for every merge field it encounters in the document or the current mail merge region.

Examples

Shows how to execute a mail merge with a data source in the form of a custom object.

void CustomDataSource()
{
    auto doc = MakeObject<Document>();
    auto builder = MakeObject<DocumentBuilder>(doc);
    builder->InsertField(u" MERGEFIELD FullName ");
    builder->InsertParagraph();
    builder->InsertField(u" MERGEFIELD Address ");

    SharedPtr<System::Collections::Generic::List<SharedPtr<ExMailMergeCustom::Customer>>> customers =
        MakeObject<System::Collections::Generic::List<SharedPtr<ExMailMergeCustom::Customer>>>();
    customers->Add(MakeObject<ExMailMergeCustom::Customer>(u"Thomas Hardy", u"120 Hanover Sq., London"));
    customers->Add(MakeObject<ExMailMergeCustom::Customer>(u"Paolo Accorti", u"Via Monte Bianco 34, Torino"));

    // To use a custom object as a data source, it must implement the IMailMergeDataSource interface.
    auto dataSource = MakeObject<ExMailMergeCustom::CustomerMailMergeDataSource>(customers);

    doc->get_MailMerge()->Execute(dataSource);

    doc->Save(ArtifactsDir + u"MailMergeCustom.CustomDataSource.docx");
}

class Customer : public System::Object
{
public:
    String get_FullName()
    {
        return pr_FullName;
    }

    void set_FullName(String value)
    {
        pr_FullName = value;
    }

    String get_Address()
    {
        return pr_Address;
    }

    void set_Address(String value)
    {
        pr_Address = value;
    }

    Customer(String aFullName, String anAddress)
    {
        set_FullName(aFullName);
        set_Address(anAddress);
    }

private:
    String pr_FullName;
    String pr_Address;
};

class CustomerMailMergeDataSource : public IMailMergeDataSource
{
public:
    String get_TableName() override
    {
        return u"Customer";
    }

    CustomerMailMergeDataSource(SharedPtr<System::Collections::Generic::List<SharedPtr<ExMailMergeCustom::Customer>>> customers) : mRecordIndex(0)
    {
        mCustomers = customers;

        // When we initialize the data source, its position must be before the first record.
        mRecordIndex = -1;
    }

    bool GetValue(String fieldName, SharedPtr<System::Object>& fieldValue) override
    {
        if (fieldName == u"FullName")
        {
            fieldValue = System::ObjectExt::Box<String>(mCustomers->idx_get(mRecordIndex)->get_FullName());
            return true;
        }
        else if (fieldName == u"Address")
        {
            fieldValue = System::ObjectExt::Box<String>(mCustomers->idx_get(mRecordIndex)->get_Address());
            return true;
        }
        else
        {
            fieldValue.reset();
            return false;
        }
    }

    bool MoveNext() override
    {
        if (!get_IsEof())
        {
            mRecordIndex++;
        }

        return !get_IsEof();
    }

    SharedPtr<IMailMergeDataSource> GetChildDataSource(String tableName) override
    {
        return nullptr;
    }

private:
    bool get_IsEof()
    {
        return mRecordIndex >= mCustomers->get_Count();
    }

    SharedPtr<System::Collections::Generic::List<SharedPtr<ExMailMergeCustom::Customer>>> mCustomers;
    int mRecordIndex;
};

See Also

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