使用libcurl开源库和Duilib做的下载文件并显示进度条的小工具

2022-11-08 10:38:01

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

使用libcurl开源库和Duilib做的下载文件并显示进度条的小工具

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：

使用libcurl开源库和Duilib做的下载文件并显示进度条的小工具

使用libcurl开源库和Duilib做的下载文件并显示进度条的小工具

下载源码Demo

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