Tk

The following table contains some commonly used Tk file commands and a summary of their usage. For more in-depth explanations and a complete listing, referred to http://www.tcl.tk/man/ or to a Tcl/Tk handbook.

tk_getOpenFile

Opens a file browser to allow you to select an existing file.

tk_getSaveFile

Opens a file browser to allow you to either enter a new file name or select an existing file. If the file exists, you are prompted to overwrite the file.

tk_chooseDirectory

Opens a file browser to allow you to either enter a new directory name or select an existing directory.

To open a file for reading, use tk_getOpenFile.

set filename [tk_getOpenFile];
puts "$filename";
Tcl returns the selected file name.

To select a file for saving, use tk_getSaveFile. The tk_getSaveFile command handles everything for you including write permissions, selecting existing files, creating directories on the fly, and all other functionality included in standard file browser. tk_getSaveFile returns the selected filename but does not actually create a file.

set filename [tk_getSaveFile];
puts "$filename";
Tcl returns the selected file name.

To make file selections easier for the user, the tk_getOpenFile and tk_getSaveFile commands provide a -filetypes option. This option takes only one parameter which is a list of file types. Each file type is also a list containing two parameters which are a file type description and the file extension. Since spaces are treated as list separators, parameters that contain spaces must be contained within quotes or braces. A file types parameter might look like:

{{"File Description 1" *.ext1} {"File Description 2" *.ext2}};

set filetypes "{{OptiStruct files} {*.fem *.parm}} {{All Files} {*.*}}";
set filename [tk_getOpenFile -filetypes $filetypes];
puts $filename;
Tcl returns the selected file name.

Now that you have a full path to a file, you will probably need to find out the file name without the full path, which directory the file is located in, and the file extension. If you selected a file named C:/My_files/readme.txt from the tk_getOpenFile command:

set filename [tk_getOpenFile];
C:/My_files/readme.txt

file dirname $filename;
C:/My_files

file tail $filename;
readme.txt

file extension $filename;
.txt

file rootname $filename;
readme

set path_list [file split $filename];
C:/ My_files readme.txt

lindex $path_list end;
readme.txt