vs使用libcurl(static library)，link时报错：
error LNK2001: unresolved external symbol __imp__curl_easy_perform
error LNK2001: unresolved external symbol __imp__curl_easy_setopt
error LNK2001: unresolved external symbol __imp__curl_easy_init
error LNK2001: unresolved external symbol __imp__curl_easy_cleanup
1、项目属性->link->input:
libcurl.lib ws2_32.lib winmm.lib wldap32.lib
2、项目属性->C/C++->Preprocessor->Definitions 增加:
BUILDING_LIBCURL
HTTP_ONLY