正如Beaker和Ander Biguri所建议的那样，您可以通过获取所有文件，然后进行排序来实现这一点。
下面是相关代码，其中包含内嵌的说明：

baseDir = 'C:\mydir';

files = dir(baseDir);
files( [ files.isdir] ) = [];   % This removes directories, especially '.' and '..'.

fileNames = cell(size(files));  % In this cell, we store the file names.
fileExt   = cell(size(files));  % In this cell, we store the file extensions.
for k = 1 : numel(fileNames )
    cf = files(k);
    fileNames{k}      = [ cf.folder filesep cf.name];  % Get file name
    [~,~, fileExt{k}] = fileparts( cf.name );          % Get extension
end

[~,idx] = sort( fileExt );    % Get index to sort by extension
fileNames = fileNames( idx ); % Do the actual sorting