Browse for Files, Folders, Computers and Printers
Using the SHBrowseForFolder API you can invoke a
system dialog used to browse for files and folders on your hard drive as well
as network computers and printers. While this method of browsing your
file system does not provide as many options as using the Common Dialog
control, it is fast and easy to use. What it does do is allow you to select
computers and printers. You can set flags that tell the system what to browse
for. Windows will enable and disable the OK button automatically depending on
the flags set and the item selected.
Download Source Code
The main component of this program is the SHBrowseForFolder
API. SHBrowseForFolder displays a dialog box
enabling the user to select a shell folder. To do this we must first populate a
BrowseInfo structure which is used by the API. Two of the main
elements of BrowseInfo are the lpszTitle
and ulFlags fields. As the name implies,
lpszTitle contains the title to display at the top of the dialog.
The ulFlags element get the value which determines
what the dialog displays and allows the user to select.
For example, to browse for folders only, ulFlags should
contain the value BIF_RETURNONLYFSDIRS. To browse
for both folders and files the field should be set to BIF_RETURNONLYFSDIRS
Or BIF_BROWSEINCLUDEFILES. Once
BrowseInfo is populated, the SHBrowseForFolder
API is called to display the dialog.
You can navigate through the dialog but Windows will only allow you to select
the type of item indicated by ulFlags. Once you
click an item SHBrowseForFolder returns with ID
that item. The ID must then be converted into a string representing the path to
the chosen item. This is where the SHGetPathFromIDList
API comes in. This function converts an item identifier to a file system path.
You can specify the folder to start in to a certain degree. You cannot specify
just any folder. It must be a Window's Special Folder
such as the Desktop, Program Files, Recycle Bin, Windows directory,...
Window's refers to special folders by means of an ID. A call to
SHGetSpecialFolderLocation passing the handle of your form and a
flag identifying the folder to locate populates an ITEMIDLIST
structure with the ID of the folder. This ID can then be assigned to the
pIDLRoot element of the BrowseInfo structure.
Finally, the item identifier list returned by SHBrowseForFolder
must be freed via a call to the CoTaskMemFree function.
Some of the flags and features may not be available depending on the version of
Shell32.dll you have installed. Check out MSDN (there is a link on
my Microsoft Links page) for details.
Download the source code and press F5 to run the program. Select the option to
browse for then click Browse. Experiment by setting different flag
combinations.
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