计算文件c＃中每个唯一单词的出现

Question

I am writing a simple console application to would allow me to count the occurrence of each unique word. for example the console will allow the user to type a sentence, once press enter the system should count the number of time each words occurs. so far I can only count characters. any help would be appreciated.

class Program
{
    static void Main(string[] args)
    {

        Console.WriteLine("Please enter string");
        string input = Convert.ToString(Console.ReadLine());
        Dictionary<string, int> objdict = new Dictionary<string, int>();
        foreach (var j in input)
        {
            if (objdict.ContainsKey(j.ToString()))
            {
                objdict[j.ToString()] = objdict[j.ToString()] + 1;
            }
            else
            {
                objdict.Add(j.ToString(), 1);
            }
        }
        foreach (var temp in objdict)
        {
            Console.WriteLine("{0}:{1}", temp.Key, temp.Value);
        }
        Console.ReadLine();
    }
}

Answer 1

Try this method:

private void countWordsInALIne(string line, Dictionary<string, int> words)
{
    var wordPattern = new Regex(@"\w+");

    foreach (Match match in wordPattern.Matches(line))
    {
        int currentCount=0;
        words.TryGetValue(match.Value, out currentCount);

        currentCount++;
        words[match.Value] = currentCount;
    }
}

Call the above method like this:

var words = new Dictionary<string, int>(StringComparer.CurrentCultureIgnoreCase);

countWordsInALine(line, words);

In the words dictionary you will find the words (key) along with its occurance frequency (value).

Answer 2

Just call Split method passing single space (assuming word is seperated by single space) and it would give collection of each word then iterate over each element of collection with the same logic you were having.

class Program
{
    static void Main(string[] args)
    {

        Console.WriteLine("Please enter string");
        string input = Convert.ToString(Console.ReadLine());
        Dictionary<string, int> objdict = new Dictionary<string, int>();
        foreach (var j in input.Split(" "))
        {
            if (objdict.ContainsKey(j))
            {
                objdict[j] = objdict[j] + 1;
            }
            else
            {
                objdict.Add(j, 1);
            }
        }
        foreach (var temp in objdict)
        {
            Console.WriteLine("{0}:{1}", temp.Key, temp.Value);
        }
        Console.ReadLine();
    }
}

Answer 3

You need to split the string on spaces (or any other characters which you consider to delimit words). Try changing the loop to this:

foreach (string Word in input.Split(' ')) {

}

Answer 4

Try this...

var theList = new List<string>() { "Alpha", "Alpha", "Beta", "Gamma", "Delta" };

theList.GroupBy(txt => txt)
    .Where(grouping => grouping.Count() > 1)
    .ToList()
    .ForEach(groupItem => Console.WriteLine("{0} duplicated {1} times with these values {2}",
         groupItem.Key,
         groupItem.Count(),
         string.Join(" ", groupItem.ToArray())));
        Console.ReadKey();

http://omegacoder.com/?p=792

Answer 5

Might I suggest a ternary-tree to make things efficient?

Here's a link to a C# implementation: http://igoro.com/archive/efficient-auto-complete-with-a-ternary-search-tree/

After first inserting into the tree, you could simply call "Contains" with one of the implementations above to make things quick