The easiest way I've found on doing this would be something like the following:
%Get information about what's inside your folder.
myfiles = dir('C:\The_file_location_folder');
%Get the filenames and folders of all files and folders inside the folder
%of your choice.
filenames={myfiles(:).name}';
filefolders={myfiles(:).folder}';
%Get only those files that have a csv extension and their corresponding
%folders.
csvfiles=filenames(endsWith(filenames,'.csv'));
csvfolders=filefolders(endsWith(filenames,'.csv'));
%Make a cell array of strings containing the full file locations of the
%files.
files=fullfile(csvfolders,csvfiles);
Now after this you can use whatever you'd like to loop through those files and open them, whether it be xlsread() or fopen() with textscan().
Personally, I prefer using textscan() to open .csv files because it takes quite a bit less time, and it sounds as though you may have a large number of files. However, textscan does have its drawbacks, and if the files were created in Excel, it may not always format whatever's inside the files properly, not allowing you to actually get the information you desire out of it.
See these examples for textscan() and xlsread().
textscan():
xlsread()
You may also find other resources on how to read in csv files quickly, such as csvread(). However, I've always preferred to design my own routines to read in the information I am looking for.
