解决error LNK2001: unresolved external symbol

解决error LNK2001: unresolved external symbol

(1) vc网络编程中遇到一个编译问题，原来是少了WSOCK32.LIB。
在 project-->settings-->Link-->Object/Library modules 中加入库WSOCK32.LIB即可。
在VC中进行WINSOCK的API编程开发的时候，需要在项目中使用下面三个文件，否则会出现编译错误。 　　

1．WINSOCK.H: 这是WINSOCK API的头文件，需要包含在项目中。 　　

2．WSOCK32.LIB: WINSOCK API连接库文件。在使用中，一定要把它作为项目的非缺省的连接库包含到项目文件中去。 　　

3．WINSOCK.DLL: WINSOCK的动态连接库，位于WINDOWS的安装目录下。
--------------------Configuration: Example1 - Win32 Debug--------------------

Linking... error LNK2001: unresolved external symbol _connect@12

error LNK2001: unresolved external symbol _htons@4

error LNK2001: unresolved external symbol _inet_addr@4

error LNK2001: unresolved external symbol _socket@12

error LNK2001: unresolved external symbol _closesocket@4

error LNK2001: unresolved external symbol _send@16

error LNK2001: unresolved external symbol _recv@16

error LNK2001: unresolved external symbol _WSAAsyncSelect@16

error LNK2001: unresolved external symbol _accept@12

error LNK2001: unresolved external symbol _listen@8

error LNK2001: unresolved external symbol _bind@12
(2) vc数据库SQL编程中遇到一个问题，原来是少了odbc32.lib。
在 project-->settings-->Link-->Object/Library modules 中加入库odbc32.lib 即可。

mfc程序调用了odbc api,连接时出错: error    LNK2001:    unresolved    external    symbol    _SQLConnect@28

error    LNK2001:    unresolved    external    symbol    _SQLFetch@4   

error    LNK2001:    unresolved    external    symbol    _SQLBindCol@24   

error    LNK2001:    unresolved    external    symbol    _SQLFreeHandle@8   

error   LNK2001:   unresolved   external   symbol   _SQLExecDirect@12  

error   LNK2001:   unresolved   external   symbol   _SQLAllocHandle@12  

error    LNK2001:    unresolved    external    symbol    _SQLSetEnvAttr@16    error    LNK2001:    unresolved    external    symbol    _SQLDisconnect@4   
(3) vc    OpenCV图像处理编程中遇到一个问题，原来是少了cv.lib cvaux.lib cxcore.lib highgui.lib。
在 project-->settings-->Link-->Object/Library modules 中加入库cv.lib cvaux.lib cxcore.lib highgui.lib 即可。 error LNK2001: unresolved external symbol _cvReleaseImage error LNK2001: unresolved external symbol _cvWaitKey error LNK2001: unresolved external symbol _cvDrawContours error LNK2001: unresolved external symbol _cvReleaseMemStorage error LNK2001: unresolved external symbol _cvDestroyWindow error LNK2001: unresolved external symbol _cvFindContours error LNK2001: unresolved external symbol _cvCvtColor error LNK2001: unresolved external symbol _cvCreateImage error LNK2001: unresolved external symbol _cvGetSize error LNK2001: unresolved external symbol _cvShowImage error LNK2001: unresolved external symbol _cvLoadImage error LNK2001: unresolved external symbol _cvNamedWindow error LNK2001: unresolved external symbol _cvCreateMemStorage
(4) vc OpenGL三维编程中遇到一个问题，原来是少了OpenGL32.lib GLu32.lib GLaux.lib。
在 project-->settings-->Link-->Object/Library modules 中加入库OpenGL32.lib GLu32.lib GLaux.lib 即可。 error LNK2001: unresolved external symbol _gluPerspective@32 error LNK2001: unresolved external symbol _gluLookAt@72 error LNK2001: unresolved external symbol __imp__glLoadIdentity@0 error LNK2001: unresolved external symbol __imp__glMatrixMode@4 error LNK2001: unresolved external symbol __imp__glViewport@16 error LNK2001: unresolved external symbol __imp__glHint@8 error LNK2001: unresolved external symbol __imp__glDepthFunc@4 error LNK2001: unresolved external symbol __imp__glEnable@4 error LNK2001: unresolved external symbol __imp__glClearDepth@8 error LNK2001: unresolved external symbol __imp__glClearColor@16 error LNK2001: unresolved external symbol __imp__glShadeModel@4 error LNK2001: unresolved external symbol __imp__glEnd@0 error LNK2001: unresolved external symbol __imp__glVertex3f@12 error LNK2001: unresolved external symbol __imp__glBegin@4 error LNK2001: unresolved external symbol __imp__glTranslatef@12 error LNK2001: unresolved external symbol __imp__glClear@4 error LNK2001: unresolved external symbol __imp__wglDeleteContext@4 error LNK2001: unresolved external symbol __imp__wglMakeCurrent@8 error LNK2001: unresolved external symbol __imp__wglCreateContext@4
(5) vc VFW视频采集编程中遇到一个问题，原来是少了VFW32.Lib
在 project-->settings-->Link-->Object/Library modules 中加入库VFW32.Lib 即可。 error LNK2001: unresolved external symbol _capCreateCaptureWindowA@32