{"id":93001,"date":"2016-02-08T07:00:00","date_gmt":"2016-02-08T22:00:00","guid":{"rendered":"https:\/\/blogs.msdn.microsoft.com\/oldnewthing\/?p=93001"},"modified":"2019-03-13T10:30:06","modified_gmt":"2019-03-13T17:30:06","slug":"20160208-00","status":"publish","type":"post","link":"https:\/\/devblogs.microsoft.com\/oldnewthing\/20160208-00\/?p=93001","title":{"rendered":"How can I get the canonical name for a known folder?"},"content":{"rendered":"

A customer had a question about the IKnown­Folder::Get­Folder­By­Name<\/code><\/a> method: “What is the canonical name for the Documents folder? We tried \"Documents\"<\/tt> but that didn’t work.” <\/p>\n

One question that comes to mind is why you are using this method to begin with. If you already know that you want the Documents folder, then use IKnown­Folder::Get­Folder<\/code><\/a> and pass FOLDERID_Documents<\/code>. Just go straight for the thing you want; don’t play around with canonical names. <\/p>\n

But okay, let’s answer the question anyway. The way to get the canonical name for a folder is to ask it! <\/p>\n

Today’s smart pointer library is (rolls dice) ATL! <\/p>\n

\n#include <windows.h>\n#include <shlobj.h>\n#include <stdio.h> \/\/ horrors! Mixing stdio and C++!\n#include <atlbase.h>\n#include <atlalloc.h>\n\nint __cdecl main()\n{\n CCoInitialize<\/a> init;\n\n CComPtr<IKnownFolderManager> mgr;\n CoCreateInstance(CLSID_KnownFolderManager, 0,\n                  CLSCTX_ALL, IID_PPV_ARGS(&mgr));\n\n CComPtr<IKnownFolder> kf;\n mgr->GetFolder(FOLDERID_Documents, &kf);\n KNOWNFOLDER_DEFINITION def;\n kf->GetFolderDefinition(&def);\n printf(\"%ls\\n\", def.pszName);\n FreeKnownFolderDefinitionFields(&def);\n return 0;\n}\n<\/pre>\n
Run this program and it tells you that the canonical name is Personal<\/tt>. <\/p>\n
Let’s go one step further: Let’s print the canonical names for all<\/i> of the known folders. <\/p>\n
\n#include <windows.h>\n#include <shlobj.h>\n#include <stdio.h> \/\/ horrors! Mixing stdio and C++!\n#include <atlbase.h>\n#include <atlalloc.h>\n\nint __cdecl main()\n{\n CCoInitialize<\/a> init;\n\n CComPtr<IKnownFolderManager> mgr;\n CoCreateInstance(CLSID_KnownFolderManager, 0,\n                  CLSCTX_ALL, IID_PPV_ARGS(&mgr));\n\n UINT count;\n CComHeapPtr<KNOWNFOLDERID> kfids;\n mgr->GetFolderIds(&kfids, &count);\n for (UINT index = 0; index < count; index++) {<\/font>\n  CComPtr<IKnownFolder> kf;\n  mgr->GetFolder(kfids[index]<\/font>, &kf);\n  KNOWNFOLDER_DEFINITION def;\n  kf->GetFolderDefinition(&def);\n  printf(\"%ls\\n\", def.pszName);\n  FreeKnownFolderDefinitionFields(&def);\n }<\/font>\n return 0;\n}\n<\/pre>\n","protected":false},"excerpt":{"rendered":"
You ask it.<\/p>\n","protected":false},"author":1069,"featured_media":111744,"comment_status":"open","ping_status":"closed","sticky":false,"template":"","format":"standard","meta":{"_acf_changed":false,"footnotes":""},"categories":[1],"tags":[25],"class_list":["post-93001","post","type-post","status-publish","format-standard","has-post-thumbnail","hentry","category-oldnewthing","tag-code"],"acf":[],"blog_post_summary":"
You ask it.<\/p>\n","_links":{"self":[{"href":"https:\/\/devblogs.microsoft.com\/oldnewthing\/wp-json\/wp\/v2\/posts\/93001","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/devblogs.microsoft.com\/oldnewthing\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/devblogs.microsoft.com\/oldnewthing\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/devblogs.microsoft.com\/oldnewthing\/wp-json\/wp\/v2\/users\/1069"}],"replies":[{"embeddable":true,"href":"https:\/\/devblogs.microsoft.com\/oldnewthing\/wp-json\/wp\/v2\/comments?post=93001"}],"version-history":[{"count":0,"href":"https:\/\/devblogs.microsoft.com\/oldnewthing\/wp-json\/wp\/v2\/posts\/93001\/revisions"}],"wp:featuredmedia":[{"embeddable":true,"href":"https:\/\/devblogs.microsoft.com\/oldnewthing\/wp-json\/wp\/v2\/media\/111744"}],"wp:attachment":[{"href":"https:\/\/devblogs.microsoft.com\/oldnewthing\/wp-json\/wp\/v2\/media?parent=93001"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/devblogs.microsoft.com\/oldnewthing\/wp-json\/wp\/v2\/categories?post=93001"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/devblogs.microsoft.com\/oldnewthing\/wp-json\/wp\/v2\/tags?post=93001"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}