我有一个存在于文件系统中的文件夹,其中包含大量 XML 文件。假设是 10,000。
我有多个 (5) Windows 服务每 30 秒检查一次该文件夹并同时处理文件。我正在尝试编写足够智能的服务进程代码,以便它可以处理并发请求以进行处理。
然而,它有时会挂在几个文件上。
E[The process cannot access the file '...' because it is being used by another process.]
我看到上面的错误在处理过程中记录了大约 1% 的文件。我可以做些什么来改进以下代码以防止这种情况发生?
class Program
{
private static string _instanceGuid;
static string InstanceGuid
{
get
{
if(_instanceGuid == null)
{
_instanceGuid = Guid.NewGuid().ToString();
}
return _instanceGuid;
}
}
static void Main(string[] args)
{
string[] sourceFiles = Directory.GetFiles("c\\temp\\source\\*.xml")
.OrderBy(d => new FileInfo(d).CreationTime).ToArray();
foreach (string file in sourceFiles)
{
var newFileName = string.Empty;
try
{
// first we'll rename in this way try and
// i would think it should throw an exception and move on to the next file. an exception being thrown means that file should already be processing by another service.
newFileName = string.Format("{0}.{1}", file, InstanceGuid);
File.Move(file, newFileName);
var xml = string.Empty;
using (var s = new FileStream(newFileName, FileMode.Open, FileAccess.Read, FileShare.None))
using (var tr = new StreamReader(s))
{
xml = tr.ReadToEnd();
}
// at this point we have a valid XML save to db
}
catch (FileNotFoundException ex)
{
// continue onto next source file
}
catch (Exception ex)
{
// log error
}
}
}
}