vs2022 c++使用curl+libxml2库获取网站标题demo

开发环境 windows10 64位

• 首先需要安装vcpkg工具。 开始使用 vcpkg
• 创建项目
• 打开CMD进行安装curl和libxml2库

vcpkg install curl:x64-windows
vcpkg install libxml2:x64-windows

• 安装完成后执行vcpkg integrate install，让vs2022可以识别该lib库。
• 先填一下坑，使用VS2022，打开X:\vcpkg\vcpkg\installed\x64-windows\include\iconv.h文件，然后Ctrl+A全选代码，菜单文件->iconv.h 另存为-> 选择编码保存->选择UNICODE 代码页 1200 确定保存。
  
  编码保存

UNICODE 代码页 1200

• Demo main.cpp代码，参考地址 https://curl.se/libcurl/c/htmltitle.html

#include 
#include 
#include 
#include 
#include
#include 

# pragma warning (disable:4819)

//
//  Case-insensitive string comparison
//

#ifdef _MSC_VER
#define COMPARE(a, b) (!_stricmp((a), (b)))
#else
#define COMPARE(a, b) (!strcasecmp((a), (b)))
#endif

//
//  libxml callback context structure
//

struct Context
{
    Context() : addTitle(false) { }

    bool addTitle;
    std::string title;
};

//
//  libcurl variables for error strings and returned data

static char errorBuffer[CURL_ERROR_SIZE];
static std::string buffer;

//
//  libcurl write callback function
//

static int writer(char* data, size_t size, size_t nmemb,
    std::string* writerData)
{
    if (writerData == NULL)
        return 0;

    writerData->append(data, size * nmemb);

    return size * nmemb;
}

//
//  libcurl connection initialization
//

static bool init(CURL*& conn, char* url)
{
    CURLcode code;

    conn = curl_easy_init();

    if (conn == NULL) {
        fprintf(stderr, "Failed to create CURL connection\n");
        exit(EXIT_FAILURE);
    }

    code = curl_easy_setopt(conn, CURLOPT_ERRORBUFFER, errorBuffer);
    if (code != CURLE_OK) {
        fprintf(stderr, "Failed to set error buffer [%d]\n", code);
        return false;
    }

    code = curl_easy_setopt(conn, CURLOPT_URL, url);
    if (code != CURLE_OK) {
        fprintf(stderr, "Failed to set URL [%s]\n", errorBuffer);
        return false;
    }

    code = curl_easy_setopt(conn, CURLOPT_FOLLOWLOCATION, 1L);
    if (code != CURLE_OK) {
        fprintf(stderr, "Failed to set redirect option [%s]\n", errorBuffer);
        return false;
    }

    code = curl_easy_setopt(conn, CURLOPT_WRITEFUNCTION, writer);
    if (code != CURLE_OK) {
        fprintf(stderr, "Failed to set writer [%s]\n", errorBuffer);
        return false;
    }

    code = curl_easy_setopt(conn, CURLOPT_WRITEDATA, &buffer);
    if (code != CURLE_OK) {
        fprintf(stderr, "Failed to set write data [%s]\n", errorBuffer);
        return false;
    }

    return true;
}

//
//  libxml start element callback function
//

static void StartElement(void* voidContext,
    const xmlChar* name,
    const xmlChar** attributes)
{
    Context* context = static_cast(voidContext);

    if (COMPARE(reinterpret_cast(name), "TITLE")) {
        context->title = "";
        context->addTitle = true;
    }
    (void)attributes;
}

//
//  libxml end element callback function
//

static void EndElement(void* voidContext,
    const xmlChar* name)
{
    Context* context = static_cast(voidContext);

    if (COMPARE(reinterpret_cast(name), "TITLE"))
        context->addTitle = false;
}

//
//  Text handling helper function
//

static void handleCharacters(Context* context,
    const xmlChar* chars,
    int length)
{
    if (context->addTitle)
        context->title.append(reinterpret_cast(chars), length);
}

//
//  libxml PCDATA callback function
//

static void Characters(void* voidContext,
    const xmlChar* chars,
    int length)
{
    Context* context = static_cast(voidContext);

    handleCharacters(context, chars, length);
}

//
//  libxml CDATA callback function
//

static void cdata(void* voidContext,
    const xmlChar* chars,
    int length)
{
    Context* context = static_cast(voidContext);

    handleCharacters(context, chars, length);
}

//
//  libxml SAX callback structure
//

static htmlSAXHandler saxHandler =
{
  NULL,
  NULL,
  NULL,
  NULL,
  NULL,
  NULL,
  NULL,
  NULL,
  NULL,
  NULL,
  NULL,
  NULL,
  NULL,
  NULL,
  StartElement,
  EndElement,
  NULL,
  Characters,
  NULL,
  NULL,
  NULL,
  NULL,
  NULL,
  NULL,
  NULL,
  cdata,
  NULL
};

//
//  Parse given (assumed to be) HTML text and return the title
//

static void parseHtml(const std::string& html,
    std::string& title)
{
    htmlParserCtxtPtr ctxt;
    Context context;

    ctxt = htmlCreatePushParserCtxt(&saxHandler, &context, "", 0, "",
        XML_CHAR_ENCODING_NONE);

    htmlParseChunk(ctxt, html.c_str(), html.size(), 0);
    htmlParseChunk(ctxt, "", 0, 1);

    htmlFreeParserCtxt(ctxt);

    title = context.title;
}

int main(int argc, char* argv[])
{
    CURL* conn = NULL;
    CURLcode code;
    std::string title;

    // Ensure one argument is given

    if (argc != 2) {
        fprintf(stderr, "Usage: %s \n", argv[0]);
        exit(EXIT_FAILURE);
    }

    curl_global_init(CURL_GLOBAL_DEFAULT);

    // Initialize CURL connection

    if (!init(conn, argv[1])) {
        fprintf(stderr, "Connection initializion failed\n");
        exit(EXIT_FAILURE);
    }

    // Retrieve content for the URL

    code = curl_easy_perform(conn);
    curl_easy_cleanup(conn);

    if (code != CURLE_OK) {
        fprintf(stderr, "Failed to get '%s' [%s]\n", argv[1], errorBuffer);
        exit(EXIT_FAILURE);
    }

    // Parse the (assumed) HTML code
    parseHtml(buffer, title);

    // Display the extracted title
    printf("Title: %s\n", title.c_str());

    return EXIT_SUCCESS;
}

项目->属性->如下图设置。关闭所有警告

关闭所有警告

• 测试结果

  
  
  测试结果