我试图使用Directory.GetFiles()方法检索多种类型的文件列表,如mp3的和jpg的。以下两种方法我都试过了,但都没有成功:
Directory.GetFiles("C:\\path", "*.mp3|*.jpg", SearchOption.AllDirectories);
Directory.GetFiles("C:\\path", "*.mp3;*.jpg", SearchOption.AllDirectories);
有没有办法一次就能搞定?
我试图使用Directory.GetFiles()方法检索多种类型的文件列表,如mp3的和jpg的。以下两种方法我都试过了,但都没有成功:
Directory.GetFiles("C:\\path", "*.mp3|*.jpg", SearchOption.AllDirectories);
Directory.GetFiles("C:\\path", "*.mp3;*.jpg", SearchOption.AllDirectories);
有没有办法一次就能搞定?
当前回答
下面的函数搜索多个以逗号分隔的模式。你也可以指定一个排除,例如:"!web。Config”将搜索所有文件并排除“web.config”。模式可以混合使用。
private string[] FindFiles(string directory, string filters, SearchOption searchOption)
{
if (!Directory.Exists(directory)) return new string[] { };
var include = (from filter in filters.Split(new char[] { ',' }, StringSplitOptions.RemoveEmptyEntries) where !string.IsNullOrEmpty(filter.Trim()) select filter.Trim());
var exclude = (from filter in include where filter.Contains(@"!") select filter);
include = include.Except(exclude);
if (include.Count() == 0) include = new string[] { "*" };
var rxfilters = from filter in exclude select string.Format("^{0}$", filter.Replace("!", "").Replace(".", @"\.").Replace("*", ".*").Replace("?", "."));
Regex regex = new Regex(string.Join("|", rxfilters.ToArray()));
List<Thread> workers = new List<Thread>();
List<string> files = new List<string>();
foreach (string filter in include)
{
Thread worker = new Thread(
new ThreadStart(
delegate
{
string[] allfiles = Directory.GetFiles(directory, filter, searchOption);
if (exclude.Count() > 0)
{
lock (files)
files.AddRange(allfiles.Where(p => !regex.Match(p).Success));
}
else
{
lock (files)
files.AddRange(allfiles);
}
}
));
workers.Add(worker);
worker.Start();
}
foreach (Thread worker in workers)
{
worker.Join();
}
return files.ToArray();
}
用法:
foreach (string file in FindFiles(@"D:\628.2.11", @"!*.config, !*.js", SearchOption.AllDirectories))
{
Console.WriteLine(file);
}
其他回答
对于。net 4.0及更高版本,
var files = Directory.EnumerateFiles("C:\\path", "*.*", SearchOption.AllDirectories)
.Where(s => s.EndsWith(".mp3") || s.EndsWith(".jpg"));
对于。net的早期版本,
var files = Directory.GetFiles("C:\\path", "*.*", SearchOption.AllDirectories)
.Where(s => s.EndsWith(".mp3") || s.EndsWith(".jpg"));
编辑:请阅读评论。Paul Farry提出的改进,以及Christian提出的记忆/性能问题。K点都很重要。
Using GetFiles search pattern for filtering the extension is not safe!! For instance you have two file Test1.xls and Test2.xlsx and you want to filter out xls file using search pattern *.xls, but GetFiles return both Test1.xls and Test2.xlsx I was not aware of this and got error in production environment when some temporary files suddenly was handled as right files. Search pattern was *.txt and temp files was named *.txt20181028_100753898 So search pattern can not be trusted, you have to add extra check on filenames as well.
还有一个下降解决方案,似乎没有任何内存或性能开销,而且相当优雅:
string[] filters = new[]{"*.jpg", "*.png", "*.gif"};
string[] filePaths = filters.SelectMany(f => Directory.GetFiles(basePath, f)).ToArray();
for
var exts = new[] { "mp3", "jpg" };
你可以:
public IEnumerable<string> FilterFiles(string path, params string[] exts) {
return
Directory
.EnumerateFiles(path, "*.*")
.Where(file => exts.Any(x => file.EndsWith(x, StringComparison.OrdinalIgnoreCase)));
}
不要忘记新的。net 4目录。EnumerateFiles用于性能提升(目录和文件的区别是什么?EnumerateFiles vs Directory.GetFiles?) “IgnoreCase”应该比“ToLower”(。EndsWith("aspx", stringcompare . ordinalignorecase)而不是。tolower ().EndsWith("aspx"))
但EnumerateFiles的真正好处体现在你拆分过滤器并合并结果时:
public IEnumerable<string> FilterFiles(string path, params string[] exts) {
return
exts.Select(x => "*." + x) // turn into globs
.SelectMany(x =>
Directory.EnumerateFiles(path, x)
);
}
如果你不需要将它们转换为glob(即exts = new[] {"*.mp3", "*.jpg"}),它会变得更快一些。
基于以下LinqPad测试的性能评估(注意:Perf只是重复委托10000次) https://gist.github.com/zaus/7454021
(从'duplicate'重新发布和扩展,因为这个问题特别要求没有LINQ:多个文件扩展searchPattern for System.IO.Directory.GetFiles)
只是找到了另一种方法。仍然不是一次操作,而是把它扔出去,看看其他人是怎么想的。
private void getFiles(string path)
{
foreach (string s in Array.FindAll(Directory.GetFiles(path, "*", SearchOption.AllDirectories), predicate_FileMatch))
{
Debug.Print(s);
}
}
private bool predicate_FileMatch(string fileName)
{
if (fileName.EndsWith(".mp3"))
return true;
if (fileName.EndsWith(".jpg"))
return true;
return false;
}