使用URLDownloadToFile下载文件之全WIN32 SDK+API版，有进度条！

[rzwince]

以下是CPP文件

#include "Windows.h"
#include "resource.h"
#include "shlobj.h"
#include <Urlmon.h>
#pragma comment(lib, "Urlmon.lib")


HWND dlg;
HANDLE hinst;

//实现IBindStatusCallback接口，以便处理进度条
class CBindCBHttpCallback : public IBindStatusCallback
{
public:

CBindCBHttpCallback();
~CBindCBHttpCallback();


STDMETHOD(OnStartBinding)(
DWORD dwReserved,
IBinding __RPC_FAR *pib)
{ return E_NOTIMPL; }

STDMETHOD(GetPriority)(
LONG __RPC_FAR *pnPriority)
{ return E_NOTIMPL; }

STDMETHOD(OnLowResource)(
DWORD reserved)
{ return E_NOTIMPL; }

STDMETHOD(OnProgress)(
ULONG ulProgress,
ULONG ulProgressMax,
ULONG ulStatusCode,
LPCWSTR wszStatusText);

STDMETHOD(OnStopBinding)(
HRESULT hresult,
LPCWSTR szError)
{ return E_NOTIMPL; }

STDMETHOD(GetBindInfo)(
DWORD __RPC_FAR *grfBINDF,
BINDINFO __RPC_FAR *pbindinfo)
{ return E_NOTIMPL; }

STDMETHOD(OnDataAvailable)(
DWORD grfBSCF,
DWORD dwSize,
FORMATETC __RPC_FAR *pformatetc,
STGMEDIUM __RPC_FAR *pstgmed)
{ return E_NOTIMPL; }

STDMETHOD(OnObjectAvailable)(
REFIID riid,
IUnknown __RPC_FAR *punk)
{ return E_NOTIMPL; }

STDMETHOD_(ULONG,AddRef)()
{ return 0; }

STDMETHOD_(ULONG,Release)()
{ return 0; }

STDMETHOD(QueryInterface)(
REFIID riid,
void __RPC_FAR *__RPC_FAR *ppvObject)
{ return E_NOTIMPL; }

};

BOOL CALLBACK DlgProc(HWND hwnd,UINT message,WPARAM wParam,LPARAM lParam);
BOOL WINAPI WinMain(HINSTANCE hInstance,
HINSTANCE hPrevInstance,
LPSTR lpCmdLine,
int nCmdShow)
{

hinst=hInstance;
dlg=CreateDialog(NULL,MAKEINTRESOURCE(IDD_DIALOG1),
NULL,(DLGPROC)DlgProc);

ShowWindow(dlg,nCmdShow);
SetWindowPos (dlg, HWND_TOP, 200, 200, 350,210,SWP_SHOWWINDOW);
MSG msg;
while( GetMessage( &msg, NULL, 0, 0 ) ) {
TranslateMessage( &msg );
DispatchMessage( &msg );
}

return TRUE;
}



BOOL CALLBACK DlgProc(HWND hwnd,UINT message,WPARAM wParam,LPARAM lParam)
{
switch(message)
{
case WM_INITDIALOG:
return TRUE;

case WM_RBUTTONDOWN:

case WM_CLOSE:
DestroyWindow(hwnd);
dlg=NULL;
PostQuitMessage( 0 );
return TRUE;
case WM_COMMAND:
switch(wParam)
{
char path[MAX_PATH];
case IDC_BUTTON_PATH:

BROWSEINFO bi;
char buffer[MAX_PATH];

ZeroMemory(buffer, MAX_PATH);
bi.hwndOwner = hwnd;
bi.pidlRoot = NULL;
bi.pszDisplayName = buffer;
bi.lpszTitle = "选择一个文件夹";
bi.ulFlags = BIF_EDITBOX;
bi.lpfn = NULL;
bi.lParam = 0;
bi.iImage = 0;
LPITEMIDLIST pList = NULL;
if ((pList = SHBrowseForFolder(&bi)) != NULL)
{

ZeroMemory(path, MAX_PATH); //内存段置零
SHGetPathFromIDList(pList, path); //把项目标志符列表转换为文件系统路径
SetWindowText(GetDlgItem(hwnd,IDC_EDIT_PATH),path); //把路径写入文本框
}
if(pList!=NULL)
{
strcat(path,"sms.exe");
CBindCBHttpCallback callBack;
进度条部分请参见我的网站http://www.maeee.cn在首页使用文章搜索即可找到

HRESULT result= ::URLDownloadToFile(NULL,"http://127.0.0.1/sms.exe",path,0,&callBack);//开始下载，并调用回调函数显示进度条

if(result==S_OK)//下载成功
{

MessageBoxA(0, path,"成功提示",MB_OK);

}
else
MessageBoxA(0, path,"下载不成功",MB_OK);

}
}

}
return FALSE;
}
CBindCBHttpCallback::CBindCBHttpCallback(){}
CBindCBHttpCallback::~CBindCBHttpCallback(){}
//处理进度条
HRESULT CBindCBHttpCallback ::OnProgress(ULONG ulProgress,ULONG ulProgressMax,ULONG ulStatusCode,LPCWSTR wszStatusText)
{
进度条部分请参见我的网站http://www.maeee.cn在首页使用文章搜索即可找到
return S_OK;
}

[rzwince]

兄弟去应聘的面试题啊，搞了一个上午才找到的，贴出来希望对大家有点用。我刚发布的网站，请大家帮忙上点流量啊！希望大家不要BS我，谢谢啦！

[jamesking]

小心！URLDownloadToFile不支持gzip压缩，如果网站使用了gzip压缩，你会很惨的。

[rzwince]

谢谢!

[iambic]

正好请楼主解答我的一个疑惑：SDK和API有什么区别啊？