c++|C++通过url直接下载图片并保存 c++|c++

#include #include"down.h" #include #include #include #include using namespace std; #pragma comment(lib,"urlmon.lib") #pragma comment(lib,"ws2_32.lib") #void down(string url, string SavePath); void down(string url, string savepath) { /*time_t lt; lt = time(NULL); url = url + "?" + to_string(lt); */ size_t len = url.length(); //获取字符串长度 int nmlen = MultiByteToWideChar(CP_ACP, 0, url.c_str(), len + 1, NULL, 0); //如果函数运行成功，并且cchWideChar为零， //返回值是接收到待转换字符串的缓冲区所需求的宽字符数大小。 wchar_t* buffer = new wchar_t[nmlen]; MultiByteToWideChar(CP_ACP, 0, url.c_str(), len + 1, buffer, nmlen); //DeleteUrlCacheEntry(imgsavepath); DeleteUrlCacheEntry(buffer); HRESULT hr = URLDownloadToFile(NULL, buffer, _T(".\\temp\\0.jpg"), 0, NULL); if (hr == S_OK) { cout << "-------下载完成---------------------" << endl; } else { cout << "---------------图片下载失败---------------------------" << endl; } }

上面的方法存在一个致命问题就是占用磁盘增加，导致最后磁盘爆满，后面采用了另外一种方法

void download(const char* Url, const char* save_as) {byte Temp[MAXBLOCKSIZE]; ULONG Number = 1; FILE* stream; HINTERNET hSession = InternetOpen("RookIE/1.0", INTERNET_OPEN_TYPE_PRECONFIG, NULL, NULL, 0); if (hSession != NULL) { HINTERNET handle2 = InternetOpenUrl(hSession, Url, NULL, 0, INTERNET_FLAG_DONT_CACHE, 0); if (handle2 != NULL) {if ((stream = fopen(save_as, "wb")) != NULL) { while (Number > 0) { InternetReadFile(handle2, Temp, MAXBLOCKSIZE - 1, &Number); fwrite(Temp, sizeof(char), Number, stream); } fclose(stream); }InternetCloseHandle(handle2); handle2 = NULL; } InternetCloseHandle(hSession); hSession = NULL; } }

【c++|C++通过url直接下载图片并保存】