打开增强型图元文件并显示其内容

本部分包含一个示例，演示应用程序如何打开存储在磁盘上的增强型图元文件，并在工作区中显示关联的图片。

该示例使用 “打开 通用”对话框使用户能够从现有文件列表中选择增强的图元文件。 然后，它将所选文件的名称传递给 GetEnhMetaFile 函数，该函数返回标识文件的句柄。 此句柄将传递给 PlayEnhMetaFile 函数，以便显示图片。

LoadString(hInst, IDS_FILTERSTRING, 
     (LPSTR)szFilter, sizeof(szFilter)); 
 
// Replace occurrences of '%' string separator  
// with '\0'.  
 
for (i=0; szFilter[i]!='\0'; i++) 
{
    if (szFilter[i] == '%') 
            szFilter[i] = '\0'; 
}
 
LoadString(hInst, IDS_DEFEXTSTRING, 
     (LPSTR)szDefExt, sizeof(szFilter)); 
 
 
// Use the OpenFilename common dialog box  
// to obtain the desired filename.  

szFile[0] = '\0'; 
OPENFILENAME Ofn; 
Ofn.lStructSize = sizeof(OPENFILENAME); 
Ofn.hwndOwner = hWnd; 
Ofn.lpstrFilter = szFilter; 
Ofn.lpstrCustomFilter = (LPSTR)NULL; 
Ofn.nMaxCustFilter = 0L; 
Ofn.nFilterIndex = 1L; 
Ofn.lpstrFile = szFile; 
Ofn.nMaxFile = sizeof(szFile); 
Ofn.lpstrFileTitle = szFileTitle; 
Ofn.nMaxFileTitle = sizeof(szFileTitle); 
Ofn.lpstrInitialDir = (LPSTR) NULL; 
Ofn.lpstrTitle = (LPSTR)NULL; 
Ofn.Flags = OFN_SHOWHELP | OFN_PATHMUSTEXIST | OFN_FILEMUSTEXIST; 
Ofn.nFileOffset = 0; 
Ofn.nFileExtension = 0; 
Ofn.lpstrDefExt = szDefExt; 
 
GetOpenFileName(&Ofn); 
 
// Open the metafile.  
 
HENHMETAFILE hemf = GetEnhMetaFile(Ofn.lpstrFile); 
 
// Retrieve a handle to a window device context.  
 
HDC hDC = GetDC(hWnd); 
 
// Retrieve the client rectangle dimensions.  
 
GetClientRect(hWnd, &rct); 
 
// Draw the picture.  
 
PlayEnhMetaFile(hDC, hemf, &rct); 
 
// Release the metafile handle.  
 
DeleteEnhMetaFile(hemf); 
 
// Release the window DC.  
 
ReleaseDC(hWnd, hDC);