使用linq比较两个文本文件？

Question

我在一个文件夹中有4个文本文件,并且pattern.txt比较这些文本文件.pattern.txt我有

insert
update
delete
drop

我需要将这个文本文件与这四个文本文件进行比较,如果这些模式与该文本文件中的任何行匹配,我必须将这些行写入另一个日志文件中...我已经使用linq..i读取了这些文件需要比较那些文件和写入行号的文本文件..这是我的代码

var foldercontent = Directory.GetFiles(pathA)
                    .Select(filename => File.ReadAllText(filename))
                    .Aggregate(new StringBuilder(),
                    (sb, s) => sb.Append(s).Append(Environment.NewLine),
                    sb => sb.ToString());

 var pattern =  File.ReadAllLines(pathB).Aggregate(new StringBuilder(),
                    (sb, s) => sb.Append(s).Append(Environment.NewLine),
                    sb => sb.ToString());

using (var dest = File.AppendText(Path.Combine(_logFolderPath, "log.txt")))
            {
      //dest.WriteLine("LineNo : " + counter.ToString() + " : " + "" + line);
            }

编辑 我已经用c#来比较两个文本文件,但我需要在linq中

while ((line = file.ReadLine()) != null)
{
if (line.IndexOf(line2, StringComparison.CurrentCultureIgnoreCase) != -1)
{
dest.WriteLine("LineNo : " + counter.ToString() + " : " + " " + line.TrimStart());
}
counter++;
}
file.BaseStream.Seek(0, SeekOrigin.Begin);
counter = 1; 

Answer 1

可能有一个更简单的解决方案，但如果您确实想使用 LINQ，这至少是有效的：

var foldercontent = Directory.GetFiles(pathA)
                    .Select(filename => new
                    {
                        Filename = filename,
                        Lines = File.ReadAllLines(filename)
                    })
                    .SelectMany(file => file.Lines.Select((line, idx) => new
                    {
                        LineNumber = idx + 1,
                        Text = line,
                        FileName = file.Filename
                    }));

var pattern = File.ReadAllLines(pathB);

var result = from fileLine in foldercontent
             where pattern.Any(p => fileLine.Text.IndexOf(p, StringComparison.CurrentCultureIgnoreCase) != -1)
             select fileLine;

foreach (var match in result)
{
    System.Diagnostics.Debug.WriteLine("File: {0} LineNo: {1}: Text: {2}", match.FileName, match.LineNumber, match.Text);
}

或者，如果您愿意，您可以将其合并到一个 LINQ 查询中（但我认为这不太可读）：

var result = from fileLine in (Directory.GetFiles(pathA)
                    .Select(filename => new
                    {
                        Filename = filename,
                        Lines = File.ReadAllLines(filename)
                    })
                    .SelectMany(file => file.Lines.Select((line, idx) => new
                    {
                        LineNumber = idx + 1,
                        Text = line,
                        FileName = file.Filename
                    })))
                where File.ReadAllLines(pathB).Any(p => fileLine.Text.IndexOf(p, StringComparison.CurrentCultureIgnoreCase) != -1)
                select fileLine;