一款軟體的誕生必然是為了解決現有的需求,但隨著時間的流逝也必然會出現原始開發者沒有設想過的需求,這時原始開發者可以選擇開源(open source)或更常見的提供API和Extension/Plugin等方法,讓第三方開發者不用接觸到原始碼(source code)的情況下也能進行擴充功能的開發。然而這些擴充方法終究只屬於少數知名軟體,絕大部分的軟體在其開發過程中,通常不會優先考慮第三方開發者的擴充需求,但這又是一個十分迫切和常見的需求,因此本論文開發了一套SDK,該SDK使用嶄新的方法,讓第三方開發者無需依賴原始開發者就可以進行擴充功能的開發。 本論文開發的SDK,專注於擴充Microsoft Windows作業系統的桌面軟體。該SDK運用一個名為Parasite的透明視窗來完成擴充功能,Parasite會依附於一個名為Host的主程式視窗。Parasite可以根據Host的UI變化來顯示對應的功能,如此,第三方的開發者就可以在沒有原始碼也沒有API或Extension/Plugin的情況下開發需要的擴充功能。;The birth of a software application is inevitably driven by the need to address existing requirements. However, as time passes, unforeseen needs arise that the original developers may not have anticipated. In such cases, the original developers can choose to make the software open source or, more commonly, provide methods such as APIs and extensions/plugins, allowing third-party developers to extend the software′s functionality without having access to the source code. However, these extension methods are ultimately limited to a few well-known software applications, as the majority of software does not consider the needs of third-party developers. Nevertheless, this is a highly urgent and common requirement. Therefore, this paper has developed an SDK that utilizes innovative methods, enabling third-party developers to extend the functionality of desktop software without depending on the original developers. This paper introduces an SDK that focuses on extending desktop software for the Microsoft Windows operating system. The SDK employs a novel approach using a transparent window called "Parasite" to achieve the extension functionality. Parasite attaches itself to a main program window called the "Host." By adapting to changes in the Host′s user interface, Parasite can display corresponding functionality. Consequently, third-party developers can develop the desired extensions without the need for access to the source code or APIs and extensions/plugins.