使用libcurl开源库和Duilib做的下载文件并显示进度条的小工具

转载:http://blog.csdn.net/mfcing/article/details/43603525

转载:http://blog.csdn.net/infoworld/article/details/46646933

转载:http://blog.csdn.net/qq_25867649/article/details/52789467?locationNum=2

转载:http://www.cnblogs.com/wing-h/p/3263488.html

转载:http://blog.csdn.net/infoworld/article/details/46646933

转载:http://blog.csdn.net/xiaojun111111/article/details/53032126

转载:http://ysir.me/2015/08/05/libcurl%E5%AE%9E%E7%8E%B0%E6%96%AD%E7%82%B9%E7%BB%AD%E4%BC%A0/

转载:http://blog.csdn.net/qq_25867649/article/details/52913501

界面借用了网友mfcing,然后进行了修改

每个下载任务包含的功能:

1.任务名字

2.下载剩余时间

3.下载速度

4.下载进度百分比

5.继续下载

6.暂停下载

7.取消下载任务

一、首先扩展Duilib下载List

.h文件

#pragma once

class CDownloadListUI : public CTileLayoutUI
{
public:
     enum { SCROLL_TIMERID =  };
    CDownloadListUI(void);
    ~CDownloadListUI(void);
    virtual void DoEvent(TEventUI& event);
    void AddItem();

    /*
    @param strUrl  下载文件url地址
    @param strFileNmae 任务文件名
    */
    void AddItem(CDuiString strUrl,CDuiString strFilename);
private:
    UINT m_uButtonState;
    POINT m_ptLastMouse;
    LONG m_dwDelayDeltaY;
    DWORD m_dwDelayNum;
    DWORD m_dwDelayLeft;
};

inline double CalculateDelay(double state) {
    return pow(state, );
}

.cpp文件

#include "StdAfx.h"
#include "DownloadListUI.h"

CDownloadListUI::CDownloadListUI(void)
    :m_uButtonState()
    , m_dwDelayDeltaY()
    , m_dwDelayNum()
    , m_dwDelayLeft()
{
}

CDownloadListUI::~CDownloadListUI(void)
{
}

void CDownloadListUI::DoEvent( TEventUI& event )
{
    if( !IsMouseEnabled() && event.Type > UIEVENT__MOUSEBEGIN && event.Type < UIEVENT__MOUSEEND ) {
        if( m_pParent != NULL ) m_pParent->DoEvent(event);
        else CTileLayoutUI::DoEvent(event);
        return;
    }

    if( event.Type == UIEVENT_TIMER && event.wParam == SCROLL_TIMERID )
    {
        if( (m_uButtonState & UISTATE_CAPTURED) !=  ) {
            POINT pt = m_pManager->GetMousePos();
            LONG cy = (pt.y - m_ptLastMouse.y);
            m_ptLastMouse = pt;
            SIZE sz = GetScrollPos();
            sz.cy -= cy;
            SetScrollPos(sz);
            return;
        }
        else if( m_dwDelayLeft >  ) {
            --m_dwDelayLeft;
            SIZE sz = GetScrollPos();
            LONG lDeltaY =  (LONG)(CalculateDelay((double)m_dwDelayLeft / m_dwDelayNum) * m_dwDelayDeltaY);
            if( (lDeltaY >  && sz.cy != )  || (lDeltaY <  && sz.cy != GetScrollRange().cy ) ) {
                sz.cy -= lDeltaY;
                SetScrollPos(sz);
                return;
            }
        }
        m_dwDelayDeltaY = ;
        m_dwDelayNum = ;
        m_dwDelayLeft = ;
        m_pManager->KillTimer(this, SCROLL_TIMERID);
        return;
    }
    if( event.Type == UIEVENT_MOUSEWHEEL )
    {
        LONG lDeltaY = ;
        if( m_dwDelayNum >  ) lDeltaY =  (LONG)(CalculateDelay((double)m_dwDelayLeft / m_dwDelayNum) * m_dwDelayDeltaY);
        switch( LOWORD(event.wParam) ) {
        case SB_LINEUP:
            if( m_dwDelayDeltaY >=  ) m_dwDelayDeltaY = lDeltaY + ;
            else m_dwDelayDeltaY = lDeltaY + ;
            break;
        case SB_LINEDOWN:
            if( m_dwDelayDeltaY <=  ) m_dwDelayDeltaY = lDeltaY - ;
            else m_dwDelayDeltaY = lDeltaY - ;
            break;
        }
        if( m_dwDelayDeltaY >  ) m_dwDelayDeltaY = ;
        else if( m_dwDelayDeltaY < - ) m_dwDelayDeltaY = -;
        m_dwDelayNum = (DWORD)sqrt((double)abs(m_dwDelayDeltaY)) * ;
        m_dwDelayLeft = m_dwDelayNum;
        m_pManager->SetTimer(this, SCROLL_TIMERID, 50U);
        return;
    }
    CTileLayoutUI::DoEvent(event);
}

void CDownloadListUI::AddItem()
{
    CDialogBuilder builder;
    CContainerUI* pItem=static_cast<CContainerUI*>(builder.Create(L"Item_load.xml", ));
    if ( pItem )
    {
        int i=GetCount();
        CDuiString strText;
        strText.Format(L"%02d", i+);
        CControlUI* pControl=pItem->GetItemAt();
        if ( pControl )
            pControl->SetText(strText);
        pControl=pItem->GetItemAt();
        CProgressUI* pProgress=(CProgressUI*)pControl->GetInterface(L"Progress");
        if ( pProgress )
            pProgress->SetValue(i+);

        pControl=pItem->GetItemAt();
        if ( pControl )
        {
            strText.Format(L"%02d:%02d:%02d", ,,);
            pControl->SetText(strText);
        }

        pControl=pItem->GetItemAt();
        if ( pControl )
        {
            strText.Format(L"%dM/s", i+);
            pControl->SetText(strText);
        }

        pControl=pItem->GetItemAt();
        if ( pControl )
        {
            strText.Format(L"%d%%", i+);
            pControl->SetText(strText);
        }
        pControl=pItem->GetItemAt();
        if ( pControl )
            pControl->SetText(L"正在下载");
        pControl=pItem->GetItemAt();
        if ( pControl )
        {
            strText.Format(L"BtnLoad1%d", i);
            pControl->SetName(strText);
            pControl->SetTag(i);
        }
        pControl=pItem->GetItemAt();
        if ( pControl )
        {
            strText.Format(L"BtnLoad2%d", i);
            pControl->SetName(strText);
            pControl->SetTag(i);
        }
        pControl=pItem->GetItemAt();
        if ( pControl )
        {
            strText.Format(L"BtnLoad3%d", i);
            pControl->SetName(strText);
            pControl->SetTag(i);
        }
        Add(pItem);
    }
}

void CDownloadListUI::AddItem( CDuiString strUrl ,CDuiString strFilename)
{
    CDialogBuilder builder;
    CContainerUI* pItem=static_cast<CContainerUI*>(builder.Create(L"Item_load.xml", ));

    pItem->SetName(strUrl);

    if ( pItem )
    {
        int i=GetCount();
        CDuiString strText;
        strText.Format(L"%02d", i+);
        CControlUI* pControl=pItem->GetItemAt();
        if ( pControl )
            pControl->SetText(strText);

        pControl=pItem->GetItemAt();
        if (pControl)
        {
            pControl->SetText(strFilename);
            pControl->SetToolTip(strFilename);
        }

        pControl=pItem->GetItemAt();
        CProgressUI* pProgress=(CProgressUI*)pControl->GetInterface(L"Progress");
        if ( pProgress )
            pProgress->SetValue();

        pControl=pItem->GetItemAt();
        if ( pControl )
        {
            strText.Format(L"%d%%", );
            pControl->SetText(strText);
        }
        pControl=pItem->GetItemAt();
        if ( pControl )
            pControl->SetText(L"正在下载");
        pControl=pItem->GetItemAt();
        if ( pControl )
        {
            strText.Format(L"BtnLoad1%d", i);
            pControl->SetName(strText);
            pControl->SetTag(i);
        }
        pControl=pItem->GetItemAt();
        if ( pControl )
        {
            strText.Format(L"BtnLoad2%d", i);
            pControl->SetName(strText);
            pControl->SetTag(i);
        }
        pControl=pItem->GetItemAt();
        if ( pControl )
        {
            strText.Format(L"BtnLoad3%d", i);
            pControl->SetName(strText);
            pControl->SetTag(i);
        }
        Add(pItem);
    }
}

把任务项写到Item_load.xml中

<?xml version="1.0" encoding="UTF-8"?>
<Window>
    <Container width="430" height="40" inset="2,2,2,2"><!--Container-->
        <Label float="true" pos="4,10,30,30" align="left" font="1" textcolor="#FFF9F9F9" />
        <Label text="软件名称" float="true" pos="34,10,110,30" endellipsis="true" textcolor="#FFF9F9F9" align="left" font="0" />
        <Progress float="true" pos="110,18,230,22" bkimage="pro1.jpg" foreimage="pro2.jpg" min="0" max="100" value="0"/>
        <Label text="剩余时间" float="true" pos="110,24,160,54" textcolor="#FFF9F9F9" align="left" font="0" />
        <Label text="下载速度" float="true" pos="165,24,230,54" textcolor="#FFF9F9F9" align="left" font="0" />
        <Label text="下载进度" float="true" pos="235,14,270,54" textcolor="#FFF9F9F9" align="left" font="0" />
        <Label float="true" pos="280,14,350,54" textcolor="#FFF9F9F9" align="left" font="0" />
        <Button tooltip="取消" float="true" pos="370,16,383,28" normalimage="file='buttons.png' source='28,0,41,12'" hotimage="file='buttons.png' source='28,12,41,24'" pushedimage="file='buttons.png' source='28,24,41,36'" />
        <Button tooltip="暂停" float="true" pos="340,16,353,28" normalimage="file='buttons.png' source='14,0,27,12'" hotimage="file='buttons.png' source='14,12,27,24'" pushedimage="file='buttons.png' source='14,24,27,36'" />
        <Button tooltip="继续" visible="false" float="true" pos="340,16,353,28" normalimage="file='buttons.png' source='0,0,13,12'" hotimage="file='buttons.png' source='0,12,13,24'" pushedimage="file='buttons.png' source='0,24,13,36'" />
    </Container>
</Window>

二、把工作线程封装成一个类

.h文件

#ifndef _DOWNLOADFILETHREAD_H
#define _DOWNLOADFILETHREAD_H
#include   <windows.h>
#include   <process.h>  

typedef struct
{
    CString url;
    int current;
    CString speed;
    CString remaintime;
}PARAMS, *PPARAMS;

typedef struct
{
    CString *sender;//url
    CURL *handle;
    double* downloadFileLength;
    int* resumeByte;
}Progress_User_Data;

class CDownloadFileThread
{
public:
    CDownloadFileThread(CString url,string filename);
    ~CDownloadFileThread();

    void InitTask();

    /**
    开始运行线程
    **/
    void Start();  

    void Run(); 

    //暂停下载
    void PauseTask();

    //恢复下载
    void ResumeTask();

    //退出下载
    void ExitDownload();

    std::string UnicodeToANSI(const wstring& wstr);

    static size_t my_write_func(void *ptr, size_t size, size_t nmemb, FILE *stream);

    static int my_progress_func(void *progress_data,double t, /* dltotal */double d, /* dlnow */double ultotal,double ulnow);

    static unsigned int WINAPI ThreadFunction(LPVOID pParam); 

    static size_t nousecb(char *buffer, size_t x, size_t y, void *userdata);

    // Get the file size on the server
    double getDownloadFileLength(string url);

    // Get the local file size
    int  getLocalFileLength(string filepath);

    CString GetCurrentUrl();

private:
    HANDLE m_handle;

    HANDLE m_StartEvent;

    HANDLE m_EndEvent;

    unsigned int m_ThreadID;

    /*volatile*/ bool m_bIsCancel;//取消下载

    CURL* m_curl;//libcurl句柄

    FILE* m_outfile;//文件指针

    CString m_url;//下载地址

    string m_filename;//文件名

    double m_downloadFileLength;//服务器文件长度

    int m_resumeByte;//本地已下载的文件长度
};
#endif//_DOWNLOADFILETHREAD_H

.cpp文件

#include "stdafx.h"
#include "DownloadFileThread.h"

CDownloadFileThread::CDownloadFileThread(CString url,string filename)
:m_url(url)
,m_curl(NULL)
,m_outfile(NULL)
,m_bIsCancel(false)
,m_filename(filename)
,m_downloadFileLength(-)
,m_resumeByte(-)
{
    m_handle = (HANDLE)_beginthreadex(NULL,,ThreadFunction,(void*)this,,&m_ThreadID);

    m_StartEvent = CreateEvent(NULL,FALSE,FALSE,NULL);

    m_EndEvent = CreateEvent(NULL,FALSE,FALSE,NULL);

    curl_easy_init();
}

CDownloadFileThread::~CDownloadFileThread()
{

    SetEvent(m_EndEvent);

    if (m_handle)
    {
        CloseHandle(m_handle);
    }

    if (m_StartEvent)
    {
        CloseHandle(m_StartEvent);
    }

    if (m_EndEvent)
    {
        CloseHandle(m_EndEvent);
    }
}

void CDownloadFileThread::Start()
{
    SetEvent(m_StartEvent);
}

size_t CDownloadFileThread::my_write_func(void *ptr, size_t size, size_t nmemb, FILE *stream)
{
    size_t nWrite =fwrite(ptr, size, nmemb, stream);

    if (nWrite == )
    {
        return CURL_WRITEFUNC_PAUSE;
    }
    else
    {
        return nWrite;
    }

    //return fwrite(ptr, size, nmemb, stream);
} 

int CDownloadFileThread::my_progress_func(void *progress_data,
                     double t, /* dltotal */
                     double d, /* dlnow */
                     double ultotal,
                     double ulnow)
{
    //printf("%s %g / %g (%g %%)\n", progress_data, d, t, d*100.0/t);

    Progress_User_Data *data = static_cast<Progress_User_Data *>(progress_data);

    char text[] = {};
    //sprintf_s(text,sizeof(text),"%d",d*100.0/t);

    char timeFormat[]= {};

    CURL *easy_handle = data->handle;

    // Defaults to bytes/second
    double speed;
    string unit = "B";
    int hours,minutes,seconds;
    curl_easy_getinfo(easy_handle, CURLINFO_SPEED_DOWNLOAD, &speed); // curl_get_info必须在curl_easy_perform之后调用

    if (speed != )
    {
        double leftTime = ((*data->downloadFileLength) - d - (*data->resumeByte)) / speed;

        hours = leftTime / ;
        minutes = (leftTime - hours * ) / ;
        seconds = leftTime - hours *  - minutes * ;
    }

    sprintf_s(timeFormat, sizeof(timeFormat), "%02d:%02d:%02d", hours, minutes, seconds);

    if (speed >  *  * )
    {
        unit = "G";
        speed /=  *  * ;
    }
    else if (speed >  * )
    {
        unit = "MB";
        speed /=  * ;
    }
    else if (speed > )
    {
        unit = "KB";
        speed /= ;
    }

    sprintf_s(text,sizeof(text),"%.2f%s/s",speed, unit.c_str());

    CString* url = (CString*)(data->sender);
    PARAMS params;
    params.url = url->GetBuffer();
    params.current = d*100.0/t;
    params.speed = text;
    params.remaintime = timeFormat;

    HWND hWnd = FindWindow( NULL , L"下载管理器" );
    if (hWnd)
    {
        ::SendMessage(hWnd,WM_UPDATEPROGRESS,,(LPARAM)&params);
    }

    return ;
}

std::string CDownloadFileThread::UnicodeToANSI( const wstring& wstr )
{
    int unicodeLen = ::WideCharToMultiByte(CP_ACP,,wstr.c_str(),-,NULL,, NULL ,NULL);

    if(unicodeLen == ) return std::string("");

    char *pChar= new char[unicodeLen+];

    memset(pChar ,  , sizeof( char ) * (unicodeLen+));

    ::WideCharToMultiByte(CP_ACP,,wstr.c_str(),-,pChar,unicodeLen, NULL ,NULL);

    pChar[unicodeLen]=;

    string str = pChar;

    delete [] pChar;
    pChar=NULL;

    return str;
}

size_t CDownloadFileThread::nousecb(char *buffer, size_t x, size_t y, void *userdata)
{
    (void)buffer;
    (void)userdata;
    return x * y;
}

void CDownloadFileThread::InitTask()
{
    m_curl = curl_easy_init();
}

void CDownloadFileThread::PauseTask()
{
    m_bIsCancel = true;
     curl_easy_pause(m_curl,CURLPAUSE_RECV);
}

void CDownloadFileThread::ResumeTask()
{
    m_bIsCancel = false;
    if (m_curl)
    {
        curl_easy_pause(m_curl,CURLPAUSE_RECV_CONT);
    }
}

void CDownloadFileThread::ExitDownload()
{
    curl_easy_pause(m_curl,CURLPAUSE_RECV);

}

CString CDownloadFileThread::GetCurrentUrl()
{
    return m_url;
}
double CDownloadFileThread::getDownloadFileLength( string url )
{
    CURL *easy_handle = NULL;
    int ret = CURLE_OK;
    double size = -;

    do
    {
        easy_handle = curl_easy_init();
        if (!easy_handle)
        {
            break;
        }

        // Only get the header data
        ret = curl_easy_setopt(easy_handle, CURLOPT_URL, url.c_str());
        ret |= curl_easy_setopt(easy_handle, CURLOPT_HEADER, 1L);
        ret |= curl_easy_setopt(easy_handle, CURLOPT_NOBODY, 1L);
        ret |= curl_easy_setopt(easy_handle, CURLOPT_WRITEFUNCTION, nousecb);    // libcurl_a.lib will return error code 23 without this sentence on windows

        if (ret != CURLE_OK)
        {
            break;
        }

        ret = curl_easy_perform(easy_handle);

        if (ret != CURLE_OK)
        {
            char s[] = {};
            sprintf_s(s, sizeof(s), "error:%d:%s", ret, curl_easy_strerror(static_cast<CURLcode>(ret)));

            break;
        }

        // size = -1 if no Content-Length return or Content-Length=0
        ret = curl_easy_getinfo(easy_handle, CURLINFO_CONTENT_LENGTH_DOWNLOAD, &size);
        if (ret != CURLE_OK)
        {
            break;
        }

    } while ();

    curl_easy_cleanup(easy_handle);
    return size;
}

//C语言 下获取文件长度
int CDownloadFileThread::getLocalFileLength(string filepath)
{
    FILE *fp=fopen(filepath.c_str(),"r");
    if(!fp) return -;
    fseek(fp,0L,SEEK_END);
    int size=ftell(fp);
    fclose(fp); 

    return size;
}
void CDownloadFileThread::Run()
{
    CURLcode res;

    char *progress_data = "* ";

    m_curl = curl_easy_init();
    if(m_curl)
    {

        m_resumeByte = getLocalFileLength(m_filename);
        // Get the file size on the server
        m_downloadFileLength = getDownloadFileLength(UnicodeToANSI(m_url.GetBuffer()));

        if(m_resumeByte >= (int)m_downloadFileLength)
            return;

        m_outfile = fopen(m_filename.c_str(), "ab+");

        Progress_User_Data data = { &m_url, m_curl,&m_downloadFileLength,&m_resumeByte};

        curl_easy_setopt(m_curl, CURLOPT_URL, UnicodeToANSI(m_url.GetBuffer()).c_str());//在此要注意，此url必须是多字节
        curl_easy_setopt(m_curl, CURLOPT_TIMEOUT, );
        curl_easy_setopt(m_curl, CURLOPT_WRITEDATA, m_outfile);
        curl_easy_setopt(m_curl, CURLOPT_WRITEFUNCTION, my_write_func);
        curl_easy_setopt(m_curl, CURLOPT_NOPROGRESS, FALSE);
        curl_easy_setopt(m_curl, CURLOPT_PROGRESSFUNCTION, my_progress_func);
        curl_easy_setopt(m_curl, CURLOPT_PROGRESSDATA, &data);//给下载进度回调函数传参数，在此是指针

        res = curl_easy_perform(m_curl);

        fclose(m_outfile);
        /* always cleanup */
        curl_easy_cleanup(m_curl);
    }

}

unsigned int WINAPI CDownloadFileThread::ThreadFunction( LPVOID pParam )
{
    CDownloadFileThread* pthis = (CDownloadFileThread*)pParam;

    HANDLE hThrds[];

    hThrds[] = pthis->m_StartEvent;
    hThrds[] = pthis->m_EndEvent;

    while(true)
    {
        DWORD result = WaitForMultipleObjects(,hThrds,FALSE, INFINITE);

        if (result == WAIT_OBJECT_0)
        {
            pthis->Run();
        }
        else if (result == WAIT_OBJECT_0+)
        {
            break;
        }
    }

    return ;
}

因为下载任务比较耗时，所以在工作线程中进行下载，然后在UI线程显示进度，在此我用的是工作线程发消息给UI线程，然后进行进度显示。

1.这里要给界面上任务Item设置一个控件ID，这样更新进度，可以知道具体更新哪个任务的进度

2.界面添加任务时，创建一个下载对象，把url传给下载对象。

3.工作线程拿到下载进度后，用SendMessage发给UI线程，发送时要把下载用的url传回去(其实也可以用索引作为作为ID)

typedef struct
{
    CString url;//控件ID
    int current;//进度
    CString speed;//下载速速
    CString remaintime;//下载剩余时间
}PARAMS, *PPARAMS;

typedef struct
{
    CString *sender;//控件ID
    CURL *handle;libcurl指针
    double* downloadFileLength;//服务上文件长度
    int* resumeByte;//本地已下载文件长度
}Progress_User_Data;

通过url拿到文件名，这个不是所有的都可以拿到，因为有的url中没有名字

void GetFileNameFormUrl( char* fileName, const char* url )
{
    int urlLen = strlen(url);
    char mUrl[] = {};
    char fName[] = {};
    strcpy(mUrl, url);
    int cutIndex = ;
    int i = urlLen - , j = ;
    while(mUrl[--i] != '/');
    i++;
    while(mUrl[i] != '\0' && mUrl[i] != '?' &&mUrl[i] != '&')
    {
        fName[j++] = mUrl[i++];
    }
    fName[j] = '\0';
    strcpy(fileName, fName);

    return ;
}

更新进度的消息响应函数

LRESULT CMainWnd::OnRefresh(UINT uMsg, WPARAM wParam, LPARAM lParam,BOOL& bHandled)
{
    PARAMS* pParam = (PARAMS*)lParam;
    CDuiString strText;

    for (int i = ; i < m_pDownloadList->GetCount();i++)
    {
        CControlUI* pControl = m_pDownloadList->GetItemAt(i);

        if ( _tcscmp(pParam->url.GetBuffer(), pControl->GetName())== )
        {
            CContainerUI* pContain = static_cast<CContainerUI*>(pControl);

            CControlUI* pControl=pContain->GetItemAt();
            CProgressUI* pProgress=(CProgressUI*)pControl->GetInterface(L"Progress");
            if ( pProgress )
                pProgress->SetValue(pParam->current);

            pControl=pContain->GetItemAt();
            if ( pControl )
            {
                pControl->SetText(pParam->remaintime);
            }

            pControl=pContain->GetItemAt();
            if ( pControl )
            {

                pControl->SetText(pParam->speed.GetBuffer());
            }

            pControl=pContain->GetItemAt();
            if ( pControl )
            {
                strText.Format(L"%d%%", pParam->current);
                pControl->SetText(strText);
            }

            break;
        }
    }

    return ;
}

三、libcurl库支持下载过程中暂停，然后可以恢复下载，但在实际使用过程中遇到一个问题，暂停时间不长，可以正常恢复下载，如果暂停时间很长的话，再恢复时就没法继续下载了，这个问题还没解决。

最后效果：

下载源码Demo