파일 탐색기 등에서 파일을 드래그 & 드롭해서 내가 만든 프로그램에 놓았을 때,

WM_DROPFILES 이벤트가 발생됩니다. 이를 이용하기 위해서는 아래와 같이 코딩하면 됩니다.

1. ON_WM_DROPFILES()         // 클래스 위저드에서 WM_DROPFILES를 재정의한다.
2. DragAcceptFiles();

BEGIN_MESSAGE_MAP(CLeftView, CTreeView)
//{{AFX_MSG_MAP(CLeftView)
ON_WM_DROPFILES()         // 클래스 위저드에서 WM_DROPFILES를 재정의한다.
//}}AFX_MSG_MAP
END_MESSAGE_MAP()

void CLeftView::OnInitialUpdate() - oncreate()서 해도되고..
{
    CTreeView::OnInitialUpdate();
   

    // 파일 드래그 & 드롭을 위해 불러준다.
    DragAcceptFiles();
}

void CLeftView::OnDropFiles(HDROP hDropInfo)
{
    int nFiles;
    char szPathName[MAX_PATH];
    CString strFileName;
   
    // 드롭된 파일의 갯수
    nFiles = ::DragQueryFile( hDropInfo, 0xFFFFFFFF, szPathName, MAX_PATH );
//0xFFFFFF=-1이지?   

    for(int i = nFiles-1 ; i >= 0; i--)
    {
        // 파일의 경로 얻어옴
        ::DragQueryFile(hDropInfo, i, szPathName, MAX_PATH);
        AfxMessageBox( szPathName );
    }
   
    ::DragFinish(hDropInfo);
   
    CTreeView::OnDropFiles(hDropInfo);
}

-Drag기능 활성화
VOID DragAcceptFiles(<HWND hWnd,BOOL fAccept> or <bool>);->인자없이 쓰세요~

-HDROP에 대한 파일 경로를 얻어옴
UINT DragQueryFile(HDROP hDrop,UINT iFile,LPTSTR lpszFile,UINT cch);
hDrop:드랍될 파일들의 구조의 핸들(WParam)
iFile:드래그된 파일들의 인덱스
lpszFile:두번째에서 가리킨 인덱스의 파일 경로
cch:세번째 인자인 파일경로의 사이즈 

Error Messages

The WinINet functions return error codes where appropriate. The following errors are specific to the WinINet functions.

ERROR_FTP_DROPPED

12111
The FTP operation was not completed because the session was aborted.

ERROR_FTP_NO_PASSIVE_MODE

12112
Passive mode is not available on the server.

ERROR_FTP_TRANSFER_IN_PROGRESS

12110
The requested operation cannot be made on the FTP session handle because an operation is already in progress.

ERROR_GOPHER_ATTRIBUTE_NOT_FOUND

12137
The requested attribute could not be located.

ERROR_GOPHER_DATA_ERROR

12132
An error was detected while receiving data from the Gopher server.

ERROR_GOPHER_END_OF_DATA

12133
The end of the data has been reached.

ERROR_GOPHER_INCORRECT_LOCATOR_TYPE

12135
The type of the locator is not correct for this operation.

ERROR_GOPHER_INVALID_LOCATOR

12134
The supplied locator is not valid.

ERROR_GOPHER_NOT_FILE

12131
The request must be made for a file locator.

ERROR_GOPHER_NOT_GOPHER_PLUS

12136
The requested operation can be made only against a Gopher+ server, or with a locator that specifies a Gopher+ operation.

ERROR_GOPHER_PROTOCOL_ERROR

12130
An error was detected while parsing data returned from the Gopher server.

ERROR_GOPHER_UNKNOWN_LOCATOR

12138
The locator type is unknown.

ERROR_HTTP_COOKIE_DECLINED

12162
The HTTP cookie was declined by the server.

ERROR_HTTP_COOKIE_NEEDS_CONFIRMATION

12161
The HTTP cookie requires confirmation.

ERROR_HTTP_DOWNLEVEL_SERVER

12151
The server did not return any headers.

ERROR_HTTP_HEADER_ALREADY_EXISTS

12155
The header could not be added because it already exists.

ERROR_HTTP_HEADER_NOT_FOUND

12150
The requested header could not be located.

ERROR_HTTP_INVALID_HEADER

12153
The supplied header is invalid.

ERROR_HTTP_INVALID_QUERY_REQUEST

12154
The request made to HttpQueryInfo is invalid.

ERROR_HTTP_INVALID_SERVER_RESPONSE

12152
The server response could not be parsed.

ERROR_HTTP_NOT_REDIRECTED

12160
The HTTP request was not redirected.

ERROR_HTTP_REDIRECT_FAILED

12156
The redirection failed because either the scheme changed (for example, HTTP to FTP) or all attempts made to redirect failed (default is five attempts).

ERROR_HTTP_REDIRECT_NEEDS_CONFIRMATION

12168
The redirection requires user confirmation.

ERROR_INTERNET_ASYNC_THREAD_FAILED

12047
The application could not start an asynchronous thread.

ERROR_INTERNET_BAD_AUTO_PROXY_SCRIPT

12166
There was an error in the automatic proxy configuration script.

ERROR_INTERNET_BAD_OPTION_LENGTH

12010
The length of an option supplied to InternetQueryOption or InternetSetOption is incorrect for the type of option specified.

ERROR_INTERNET_BAD_REGISTRY_PARAMETER

12022
A required registry value was located but is an incorrect type or has an invalid value.

ERROR_INTERNET_CANNOT_CONNECT

12029
The attempt to connect to the server failed.

ERROR_INTERNET_CHG_POST_IS_NON_SECURE

12042
The application is posting and attempting to change multiple lines of text on a server that is not secure.

ERROR_INTERNET_CLIENT_AUTH_CERT_NEEDED

12044
The server is requesting client authentication.

ERROR_INTERNET_CLIENT_AUTH_NOT_SETUP

12046
Client authorization is not set up on this computer.

ERROR_INTERNET_CONNECTION_ABORTED

12030
The connection with the server has been terminated.

ERROR_INTERNET_CONNECTION_RESET

12031
The connection with the server has been reset.

ERROR_INTERNET_DIALOG_PENDING

12049
Another thread has a password dialog box in progress.

ERROR_INTERNET_DISCONNECTED

12163
The Internet connection has been lost.

ERROR_INTERNET_EXTENDED_ERROR

12003
An extended error was returned from the server. This is typically a string or buffer containing a verbose error message. Call InternetGetLastResponseInfo to retrieve the error text.

ERROR_INTERNET_FAILED_DUETOSECURITYCHECK

12171
The function failed due to a security check.

ERROR_INTERNET_FORCE_RETRY

12032
The function needs to redo the request.

ERROR_INTERNET_FORTEZZA_LOGIN_NEEDED

12054
The requested resource requires Fortezza authentication.

ERROR_INTERNET_HANDLE_EXISTS

12036
The request failed because the handle already exists.

ERROR_INTERNET_HTTP_TO_HTTPS_ON_REDIR

12039
The application is moving from a non-SSL to an SSL connection because of a redirect.

ERROR_INTERNET_HTTPS_HTTP_SUBMIT_REDIR

12052
The data being submitted to an SSL connection is being redirected to a non-SSL connection.

ERROR_INTERNET_HTTPS_TO_HTTP_ON_REDIR

12040
The application is moving from an SSL to an non-SSL connection because of a redirect.

ERROR_INTERNET_INCORRECT_FORMAT

12027
The format of the request is invalid.

ERROR_INTERNET_INCORRECT_HANDLE_STATE

12019
The requested operation cannot be carried out because the handle supplied is not in the correct state.

ERROR_INTERNET_INCORRECT_HANDLE_TYPE

12018
The type of handle supplied is incorrect for this operation.

ERROR_INTERNET_INCORRECT_PASSWORD

12014
The request to connect and log on to an FTP server could not be completed because the supplied password is incorrect.

ERROR_INTERNET_INCORRECT_USER_NAME

12013
The request to connect and log on to an FTP server could not be completed because the supplied user name is incorrect.

ERROR_INTERNET_INSERT_CDROM

12053
The request requires a CD-ROM to be inserted in the CD-ROM drive to locate the resource requested.

ERROR_INTERNET_INTERNAL_ERROR

12004
An internal error has occurred.

ERROR_INTERNET_INVALID_CA

12045
The function is unfamiliar with the Certificate Authority that generated the server's certificate.

ERROR_INTERNET_INVALID_OPERATION

12016
The requested operation is invalid.

ERROR_INTERNET_INVALID_OPTION

12009
A request to InternetQueryOption or InternetSetOption specified an invalid option value.

ERROR_INTERNET_INVALID_PROXY_REQUEST

12033
The request to the proxy was invalid.

ERROR_INTERNET_INVALID_URL

12005
The URL is invalid.

ERROR_INTERNET_ITEM_NOT_FOUND

12028
The requested item could not be located.

ERROR_INTERNET_LOGIN_FAILURE

12015
The request to connect and log on to an FTP server failed.

ERROR_INTERNET_LOGIN_FAILURE_DISPLAY_ENTITY_BODY

12174
The MS-Logoff digest header has been returned from the Web site. This header specifically instructs the digest package to purge credentials for the associated realm. This error will only be returned if INTERNET_ERROR_MASK_LOGIN_FAILURE_DISPLAY_ENTITY_BODY has been set.

ERROR_INTERNET_MIXED_SECURITY

12041
The content is not entirely secure. Some of the content being viewed may have come from unsecured servers.

ERROR_INTERNET_NAME_NOT_RESOLVED

12007
The server name could not be resolved.

ERROR_INTERNET_NEED_MSN_SSPI_PKG

12173
Not currently implemented.

ERROR_INTERNET_NEED_UI

12034
A user interface or other blocking operation has been requested.

ERROR_INTERNET_NO_CALLBACK

12025
An asynchronous request could not be made because a callback function has not been set.

ERROR_INTERNET_NO_CONTEXT

12024
An asynchronous request could not be made because a zero context value was supplied.

ERROR_INTERNET_NO_DIRECT_ACCESS

12023
Direct network access cannot be made at this time.

ERROR_INTERNET_NOT_INITIALIZED

12172
Initialization of the WinINet API has not occurred. Indicates that a higher-level function, such as InternetOpen, has not been called yet.

ERROR_INTERNET_NOT_PROXY_REQUEST

12020
The request cannot be made via a proxy.

ERROR_INTERNET_OPERATION_CANCELLED

12017
The operation was canceled, usually because the handle on which the request was operating was closed before the operation completed.

ERROR_INTERNET_OPTION_NOT_SETTABLE

12011
The requested option cannot be set, only queried.

ERROR_INTERNET_OUT_OF_HANDLES

12001
No more handles could be generated at this time.

ERROR_INTERNET_POST_IS_NON_SECURE

12043
The application is posting data to a server that is not secure.

ERROR_INTERNET_PROTOCOL_NOT_FOUND

12008
The requested protocol could not be located.

ERROR_INTERNET_PROXY_SERVER_UNREACHABLE

12165
The designated proxy server cannot be reached.

ERROR_INTERNET_REDIRECT_SCHEME_CHANGE

12048
The function could not handle the redirection, because the scheme changed (for example, HTTP to FTP).

ERROR_INTERNET_REGISTRY_VALUE_NOT_FOUND

12021
A required registry value could not be located.

ERROR_INTERNET_REQUEST_PENDING

12026
The required operation could not be completed because one or more requests are pending.

ERROR_INTERNET_RETRY_DIALOG

12050
The dialog box should be retried.

ERROR_INTERNET_SEC_CERT_CN_INVALID

12038
SSL certificate common name (host name field) is incorrect—for example, if you entered www.server.com and the common name on the certificate says www.different.com.

ERROR_INTERNET_SEC_CERT_DATE_INVALID

12037
SSL certificate date that was received from the server is bad. The certificate is expired.

ERROR_INTERNET_SEC_CERT_ERRORS

12055
The SSL certificate contains errors.

ERROR_INTERNET_SEC_CERT_NO_REV

12056

ERROR_INTERNET_SEC_CERT_REV_FAILED

12057

ERROR_INTERNET_SEC_CERT_REVOKED

12170
SSL certificate was revoked.

ERROR_INTERNET_SEC_INVALID_CERT

12169
SSL certificate is invalid.

ERROR_INTERNET_SECURITY_CHANNEL_ERROR

12157
The application experienced an internal error loading the SSL libraries.

ERROR_INTERNET_SERVER_UNREACHABLE

12164
The Web site or server indicated is unreachable.

ERROR_INTERNET_SHUTDOWN

12012
WinINet support is being shut down or unloaded.

ERROR_INTERNET_TCPIP_NOT_INSTALLED

12159
The required protocol stack is not loaded and the application cannot start WinSock.

ERROR_INTERNET_TIMEOUT

12002
The request has timed out.

ERROR_INTERNET_UNABLE_TO_CACHE_FILE

12158
The function was unable to cache the file.

ERROR_INTERNET_UNABLE_TO_DOWNLOAD_SCRIPT

12167
The automatic proxy configuration script could not be downloaded. The INTERNET_FLAG_MUST_CACHE_REQUEST flag was set.

ERROR_INTERNET_UNRECOGNIZED_SCHEME

12006
The URL scheme could not be recognized, or is not supported.

ERROR_INVALID_HANDLE

The handle that was passed to the API has been either invalidated or closed.

Header:  Declared in Winerror.h

ERROR_MORE_DATA

More data is available.

Header:  Declared in Winerror.h

ERROR_NO_MORE_FILES

No more files have been found.

Header:  Declared in Winerror.h

ERROR_NO_MORE_ITEMS

No more items have been found.

Header:  Declared in Winerror.h

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