柚子快报激活码778899分享：libcurl使用演示样例

简要说明：C++使用libcurl訪问"www.baidu.com"。获取返回码和打印出http文件

* @ libcurl使用演示样例

* @ 2014.04.29

* @ g++ -o LibCurlFunc LibCurlFunc.cpp -lcurl

#include

using namespace std;

Http请求结束的回调函数

@ 会被调用多次，有下载到数据(http文件)就回调。直到下载完

static size_t WriteFunction(void *input, size_t uSize, size_t uCount, void *avg)

{

/* cout << "[WriteFunction]:" << endl

<< "input=" << (char*)input << endl

<< "elementSize=" << uSize << endl

<< "elementCount=" << uCount << endl;*/

// 将请求返回数据input复制到avg中(avg为一開始curl_easy_setopt设置的參)

size_t uLen = uSize*uCount;

// string &sBuffer = *reinterpret_cast(avg);

// sBuffer.append(reinterpret_cast(input), uLen);

string *pStr = (string *)(avg);

pStr->append((char *)(input), uLen);

// 仅仅有返回uSize*uCount才会返回成功

return uLen;

}

int main()

{

CURL *pCurl = NULL;

CURLcode code;

/* CURLcode curl_global_init(long flags)

@ 初始化libcurl。全局仅仅需调一次

@ flags: CURL_GLOBAL_DEFAULT // 等同于CURL_GLOBAL_ALL

CURL_GLOBAL_ALL // 初始化全部的可能的调用

CURL_GLOBAL_SSL // 初始化支持安全套接字层

CURL_GLOBAL_WIN32 // 初始化win32套接字库

CURL_GLOBAL_NOTHING // 没有额外的初始化

......

code = curl_global_init(CURL_GLOBAL_DEFAULT);

if (code != CURLE_OK) {

cout << "curl_global_init() Err" << endl;

return -1;

}

/* CURL *curl_easy_init()

@ 初始化curl生成CURL *curl指针

pCurl = curl_easy_init();

if (pCurl == NULL) {

cout << "curl_easy_init() Err" << endl;

return -1;

}

string sUrl = "www.baidu.com";

curl_slist *pHeaders = NULL;

string sBuffer;

/* struct curl_slist *curl_slist_append(struct curl_slist * list, const char * string);

@ 加入Http消息头

@ 属性string：形式为name+": "+contents

string header = "username: andyawang";

pHeaders = curl_slist_append(pHeaders, header.c_str());

/* CURLcode curl_easy_setopt(CURL *handle, CURLoption option, parameter);

@ 设置下载属性及经常使用參数

curl_easy_setopt(pCurl, CURLOPT_URL, "www.baidu.com"); // 訪问的URL

curl_easy_setopt(pCurl, CURLOPT_HTTPHEADER, pHeaders); // 属性头部(要不pHeader就没用了)

curl_easy_setopt(pCurl, CURLOPT_TIMEOUT, 20); // 超时(单位S)

curl_easy_setopt(pCurl, CURLOPT_HEADER, 1); // 下载数据包含HTTP头部

curl_easy_setopt(pCurl, CURLOPT_WRITEFUNCTION, &WriteFunction); // !数据回调函数

curl_easy_setopt(pCurl, CURLOPT_WRITEDATA, &sBuffer); // !数据回调函数的參。一般为Buffer或文件fd

/* CURLcode curl_easy_perform(CURL *handle);

@ 開始下载

code = curl_easy_perform(pCurl);

if (code != CURLE_OK) {

cout << "curl_easy_perform() Err" << endl;

return -1;

}

/* CURLcode curl_easy_getinfo(CURL *curl, CURLINFO info, ... );

@ 获取下载完的相关信息

@ info：CURLINFO_RESPONSE_CODE // 获取返回的Http码

CURLINFO_TOTAL_TIME // 获取总的请求下载时间

CURLINFO_SIZE_DOWNLOAD // 获取下载的文件大小

......

long retCode = 0;

code = curl_easy_getinfo(pCurl, CURLINFO_RESPONSE_CODE , &retCode);

if (code != CURLE_OK) {

cout << "curl_easy_perform() Err" << endl;

return -1;

}

cout << "[Http Return Code] : " << retCode << endl;

cout << "[Http Context] : " << endl << sBuffer << endl;

/* void curl_easy_cleanup(CURL * handle);

@ 释放CURL *curl指针

curl_easy_cleanup(pCurl);

/* void curl_global_cleanup(void);

@ 初始化libcurl，全局也仅仅需调一次

curl_global_cleanup();

}

执行结果：

gapp_devnet_1:/data/home/andyawang/code/Components/Http # g++ -o LibCurlFunc LibCurlFunc.cpp -lcurl

gapp_devnet_1:/data/home/andyawang/code/Components/Http # ./LibCurlFunc

[Http Return Code] : 200

[Http Context] :

HTTP/1.0 200 OK

Date: Wed, 30 Apr 2014 02:41:35 GMT

Content-Type: text/html; charset=utf-8

Vary: Accept-Encoding

Set-Cookie: BAIDUID=8DD8F93E631536AD6CDC010E1A52507C:FG=1; expires=Thu, 31-Dec-37 23:55:55 GMT; max-age=2147483647; path=/; domain=.baidu.com

Set-Cookie: BDSVRTM=0; path=/

Set-Cookie: H_PS_PSSID=5695_1428_5225_6024_4760_6018_6256_6311_6269; path=/; domain=.baidu.com

P3P: CP=" OTI DSP COR IVA OUR IND COM "

Cache-Control: private

Expires: Wed, 30 Apr 2014 02:41:33 GMT

X-Powered-By: HPHP

Server: BWS/1.1

BDPAGETYPE: 1

BDQID: 0x9fcc512a0001374f

BDUSERID: 0

X-Cache: MISS from qplus_wanproxy_pub_fy1

Via: 1.0 qplus_wanproxy_pub_fy1 (squid/3.1.18)

Connection: close

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柚子快报激活码778899分享：libcurl使用演示样例