CPDF_Dictionary dict; dict.SetName("Type", "Catalog"); if (dict.KeyExist("Type")) { std::cout << "Key 'Type' exists in the dictionary!" << std::endl; }
CPDF_Dictionary stream_dict; stream_dict.SetName("Length", "123"); if (!stream_dict.KeyExist("Filter")) { stream_dict.SetName("Filter", "FlateDecode"); }This code creates a CPDF_Dictionary object for a PDF stream, sets its "Length" key to "123", and then checks if it has a "Filter" key. Since it doesn't, the code sets the "Filter" key to "FlateDecode". These examples illustrate how the KeyExist function can be used to check for the existence of keys in PDF dictionaries, and to conditionally manipulate them based on their existence or absence. The CPDF library is a package library for working with PDF documents in C++.