LinqToExcel to load Dictionary

Question

I have the following worked out but quite less than elegant. I\'d like to work this out with ToDictionary if possible. Thank you for any help as I\'m pretty new.

Answer 1

You can filter the values using a sigle LINQ query.This will return the name and number columns in the excel:

    var sampleExcel = new ExcelQueryFactory(@"I:\Book1.xlsx");
    var sampleWorksheet = from workSheet in sampleExcel.Worksheet("Sheet1") select workSheet;
    var selectedValues = from excelRow in sampleExcel.Worksheet()
       select new { name = excelRow[0], number =Convert.ToInt32(excelRow[1]) };
        foreach (var item in selectedValues)
        {
            Console.WriteLine(string.Format("Name is {0} ,number is {1}",item.name,item.number));
        }


        Dictionary<int, string> dict = new Dictionary<int, string>();

        foreach (var item in selectedValues)
        {
            dict.Add(item.number, item.name);
            Console.WriteLine(string.Format("Name is {0} ,number is {1}", item.name, item.number));
        }

Equivalent lambda expression for the above LINQ query:

var selectedValues1 = sampleExcel.Worksheet().Select(x => new { name = x[0], number = x[1] }); 

Answer 2

Have a go at this:

Dictionary<int, string> programsDict =
    excel
        .Worksheet()
        .Select(x => new { A = x[0].ToString(), B = x[1].ToString() })
        .ToArray()
        .Where(x => new [] { "Program #", "Program Title" }.Contains(x.A))
        .Buffer(2)
        .Select(x => new { title = x[0].B, number = int.Parse(x[1].B) })
        .ToDictionary(x => x.number, x => x.title);

You just need to NuGet "System.Interactive" to get the .Buffer(int) operator.

Or use this implementation:

public static IEnumerable<T[]> Buffer<T>(this IEnumerable<T> source, int count)
    =>
        source
            .Select((t, i) => new { t, i })
            .GroupBy(x => x.i / count)
            .Select(x => x.Select(y => y.t).ToArray());