System.IO.Directory.GetFiles的多个文件扩展名searchPattern

Question

什么是设置语法多个文件的扩展为searchPattern上Directory.GetFiles()？例如,使用.aspx和.ascx扩展名过滤掉文件.

// TODO: Set the string 'searchPattern' to only get files with
// the extension '.aspx' and '.ascx'.
var filteredFiles = Directory.GetFiles(path, searchPattern);

更新:LINQ不是一个选项,它必须是一个searchPattern传入GetFiles,如问题中所指定的.

Answer 1

var filteredFiles = Directory
    .GetFiles(path, "*.*")
    .Where(file => file.ToLower().EndsWith("aspx") || file.ToLower().EndsWith("ascx"))
    .ToList();

编辑2014-07-23

您可以在.NET 4.5中执行此操作以获得更快的枚举:

var filteredFiles = Directory
    .EnumerateFiles(path) //<--- .NET 4.5
    .Where(file => file.ToLower().EndsWith("aspx") || file.ToLower().EndsWith("ascx"))
    .ToList();

MSDN中的Directory.EnumerateFiles

Answer 2

我相信没有"开箱即用"的解决方案,这是Directory.GetFiles方法的限制.

编写自己的方法相当容易,这是一个例子.

代码可以是:

/// <summary>
/// Returns file names from given folder that comply to given filters
/// </summary>
/// <param name="SourceFolder">Folder with files to retrieve</param>
/// <param name="Filter">Multiple file filters separated by | character</param>
/// <param name="searchOption">File.IO.SearchOption, 
/// could be AllDirectories or TopDirectoryOnly</param>
/// <returns>Array of FileInfo objects that presents collection of file names that 
/// meet given filter</returns>
public string[] getFiles(string SourceFolder, string Filter, 
 System.IO.SearchOption searchOption)
{
 // ArrayList will hold all file names
ArrayList alFiles = new ArrayList();

 // Create an array of filter string
 string[] MultipleFilters = Filter.Split('|');

 // for each filter find mathing file names
 foreach (string FileFilter in MultipleFilters)
 {
  // add found file names to array list
  alFiles.AddRange(Directory.GetFiles(SourceFolder, FileFilter, searchOption));
 }

 // returns string array of relevant file names
 return (string[])alFiles.ToArray(typeof(string));
}

Answer 3

GetFiles只能匹配单个模式,但您可以使用Linq调用具有多个模式的GetFiles:

FileInfo[] fi = new string[]{"*.txt","*.doc"}
    .SelectMany(i => di.GetFiles(i, SearchOption.AllDirectories))
    .ToArray();

请参阅以下评论部分:http: //www.codeproject.com/KB/aspnet/NET_DirectoryInfo.aspx

Answer 4

我喜欢这种方法,因为它是可读的并且避免了目录的多次迭代:

var allowedExtensions = new [] {".doc", ".docx", ".pdf", ".ppt", ".pptx", ".xls", ".xslx"}; 
var files = Directory
    .GetFiles(folder)
    .Where(file => allowedExtensions.Any(file.ToLower().EndsWith))
    .ToList();

Answer 5

我担心你必须做这样的事情,我从这里改变了正则表达式.

var searchPattern = new Regex(
    @"$(?<=\.(aspx|ascx))", 
    RegexOptions.IgnoreCase);
var files = Directory.EnumerateFiles(path)
    .Where(f => searchPattern.IsMatch(f))
    .ToList();

Answer 6

var filteredFiles = Directory
    .EnumerateFiles(path, "*.*") // .NET4 better than `GetFiles`
    .Where(
        // ignorecase faster than tolower...
        file => file.ToLower().EndsWith("aspx")
        || file.EndsWith("ascx", StringComparison.OrdinalIgnoreCase))
    .ToList();

• 不要忘记新的.NET4 Directory.EnumerateFiles以提高性能(Directory.EnumerateFiles与Directory.GetFiles有什么区别？)
• "IgnoreCase"应该比"ToLower"更快

或者,拆分和合并你的globs可能会更快(至少它看起来更干净):

"*.ext1;*.ext2".Split(';')
    .SelectMany(g => Directory.EnumerateFiles(path, g))
    .ToList();

Answer 7

易于记忆、懒惰且可能不完美的解决方案：

Directory.GetFiles(dir, "*.dll").Union(Directory.GetFiles(dir, "*.exe"))