【CmakeLists】规范编写CmakeLits文件，以查找链接ZMQ与OpenCV库为例

配置和生成项目时，CMake将尝试查找和链接ZeroMQ和OpenCV库。如果找到，它将输出相关信息并配置项目以使用这两个库。如果未找到任一库，它将产生致命错误消息并停止配置过程。

cmake_minimum_required(VERSION 3.0)
project(YourProjectName)

# 查找 ZeroMQ 库
find_package(ZMQ REQUIRED)

# 查找 OpenCV 库
find_package(OpenCV REQUIRED)

if(ZMQ_FOUND AND OpenCV_FOUND)
    message(STATUS "ZeroMQ found (version ${ZMQ_VERSION}).")
    message(STATUS "OpenCV found (version ${OpenCV_VERSION}).")

    # 包含 ZeroMQ 头文件和 OpenCV 头文件
    include_directories(
    	${ZMQ_INCLUDE_DIRS}
    	${OpenCV_INCLUDE_DIRS}
    )
    
    # 添加可执行文件，并链接 ZeroMQ 和 OpenCV 库
    add_executable(your_executable_name your_source_files.cpp)
    target_link_libraries(your_executable_name ${ZMQ_LIBRARIES} ${OpenCV_LIBS})
    
else()
    if(NOT ZMQ_FOUND)
        message(FATAL_ERROR "ZeroMQ not found. Please install ZeroMQ and try again.")
    endif()

    if(NOT OpenCV_FOUND)
        message(FATAL_ERROR "OpenCV not found. Please install OpenCV and try again.")
    endif()
endif()