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c#csvhelper

Mapping to a Dictionary


I was trying to map a csv file so that each record would simply be a Dictionary<string,object>.

I am receiving an

ArgumentException "Not a member access;"

When I try to do this. Code included below:

public class CsvFileReader : FileReader
{
    public CsvFileReader(string path) : base(path){ }

    public IDictionary<string, object> Read()
    {
        var reader = new CsvReader(new StreamReader(Path));
        reader.Read();
        reader.Configuration.RegisterClassMap(new DictionaryClassMap(reader.FieldHeaders));
        return reader.GetRecord<Dictionary<string, object>>();
    }

    private class DictionaryClassMap : CsvClassMap<Dictionary<string, object>>
    {
        private readonly IEnumerable<string> _headers;

        public DictionaryClassMap(IEnumerable<string> headers)
        {
            _headers = headers;
        }

        public override void CreateMap()
        {
            foreach (var header in _headers)
            {
                var localHeader = header;
                Map(x => x[localHeader]);
            }
        }
    } 
}

Solution

  • Unfortunately, there currently is no support for mapping to a Dictionary.

    If you try doing GetRecords<Dictionary<string, object>>(), you will get an error.

    Types that inhererit IEnumerable cannot be auto mapped. Did you accidentally call GetRecord or WriteRecord which acts on a single record instead of calling GetRecords or WriteRecords which acts on a list of records?
    

    You can't map to a Dictionary either. In a mapping you need to specify a property of the class for the field to be mapped to. The indexer is not a member property which is why you're getting that error.

    SOLUTION:

    What you CAN do is this:

    var record = csv.GetRecord<dynamic>();
    

    You can use it as a dynamic object.

    DESIRED SOLUTION

    Internally, it uses the ExpandoObject, so you can do this.

    var dict = csv.GetRecord<dynamic>() as IDictionary<string, object>;