C# 在 LINQ 查询中区分

Question

我在更改一些代码后遇到了问题。我的想法是这样的：我正在计算文档中的单词数，但每个文档只有 1 个单词的副本，例如：

Document 1 = Smith Smith Smith Smith => Smith x1

Document 2 = Smith Alan Alan => Smith x1, Alan x1

Document 3 = John John => John x1

但铁匠总数应该：

Smith x2 (in 2 documents out of 3), Alan x1 (1 out of 3 documents), John x1 (1 out of 3 documents)

我认为它在我有一个单独的 distinct 方法之前是有效的（如果 distinct = false 也计算所有单词），现在它只产生 1.

之前的代码：

    private Dictionary<string, int> tempDict = new Dictionary<string, int>();
    private void Splitter(string[] file)
    {              
            tempDict = file
                .SelectMany(i => File.ReadAllLines(i)
                .SelectMany(line => line.Split(new[] { ' ' }, StringSplitOptions.RemoveEmptyEntries))                    
                .AsParallel()
                .Select(word => word.ToLower()) 
                .Distinct())
                .GroupBy(word => word)                    
                .ToDictionary(g => g.Key, g => g.Count());
    }

它应该被更改为 returns 字典，但在制作应用程序的过程中将其更改为以下代码：

private Dictionary<string, int> Splitter(string[] file, bool distinct, bool pairs)
{
    var query = file
        .SelectMany(i => File.ReadLines(i)
        .SelectMany(line => line.Split(new[] { ' '}, StringSplitOptions.RemoveEmptyEntries))
        .AsParallel()
        .Select(word => word.ToLower())
        .Where(word => !word.All(char.IsDigit)));
    if (distinct)
    {
        query = query.Distinct();
    }
    if (pairs)
    {
        var pairWise = query.Pairwise((first, second) => string.Format("{0} {1}", first, second));

        return query
                .Concat(pairWise)
                .GroupBy(word => word)
                .ToDictionary(g => g.Key, g => g.Count());
    }
    return query
        .GroupBy(word => word)
        .ToDictionary(g => g.Key, g => g.Count());           
}

另请注意，query = file.Distinct(); returns 只是文档的名称。所以它必须有所不同。

@编辑这就是我调用此方法的方式：

  private void EnterDocument(object sender, RoutedEventArgs e)
    {
        List<string> myFile= new List<string>();
        OpenFileDialog openFileDialog = new OpenFileDialog();
        openFileDialog.Multiselect = true;
        openFileDialog.Filter = "All files (*.*)|*.*|Text files (*.txt)|*.txt";
        if (openFileDialog.ShowDialog() == true)
        {
            foreach (string filename in openFileDialog.FileNames)
            {
                myFile.Add(filename);

            }
        }
        string[] myFiles= myFile.ToArray();
        myDatabase = Splitter(myFiles, true, false);
    }

Answer 1

Distinct() 将从您的 IEnumerable 中删除重复项，因此在以下内容之前调用它...

return query
    .GroupBy(word => word)
    .ToDictionary(g => g.Key, g => g.Count());

...将生成所有唯一单词的列表，但计数为 1。

编辑：

要解决合并所有行的问题，您可以这样做：

List<string> allFilesWords = new List<string>();
foreach (var filename in file)
{
    var fileQuery = File.ReadLines(filename)
        .SelectMany(line => line.Split(new[] { ' '}, StringSplitOptions.RemoveEmptyEntries))
        .AsParallel()
        .Select(word => word.ToLower())
        .Where(word => !word.All(char.IsDigit)));
    allFilesWords.AddRange(fileQuery.Distinct());
}
return allFilesWords
        .GroupBy(word => word)
        .ToDictionary(g => g.Key, g => g.Count());

C# 在 LINQ 查询中区分

C# Distinct in LINQ query

c#

linq

dictionary

distinct