How can I convert a DataTable to an IEnumerable<Dictionary<string, object>>? - linq

Question

I'd like to convert a DataTable to an IEnumerable<> of Dictionary<string, object>. I tried the following LINQ query,
from DataRow row in ds.Tables[0].AsEnumerable()
let rowDictionary = new Dictionary<string, object>()
from DataColumn column in row.Table.Columns.Cast<DataColumn>()
select rowDictionary.Add(column.ColumnName, row[column]).ToArray();
but I get the following error:
error CS1943: An expression of type
'System.Collections.Generic.IEnumerable<System.Data.DataColumn>' is not
allowed in a subsequent from clause in a query expression with source type
'System.Data.EnumerableRowCollection<AnonymousType#1>'. Type inference
failed in the call to 'SelectMany'.
I know I can brute-force this with a loop, but it seems like something I should be able to do in LINQ. Thanks in advance for any help!

Answer 1

I assume that what you want is a Dictionary for each row mapping column to value:
var dt = new DataTable();
var columns = dt.Columns.Cast<DataColumn>();
dt.AsEnumerable().Select(dataRow => columns.Select(column =>
new { Column = column.ColumnName, Value = dataRow[column] })
.ToDictionary(data => data.Column, data => data.Value));

Answer 2

Here is a way I do it in the Linq format
var registerdataVerify = (from o in dt.AsEnumerable()
select new
{
DataDef =o["shortName"].ToString(),
Value = Convert.ToInt32(o["valueDec"])
}).ToDictionary(n => n.DataDef, n => n.Value);

Answer 3

Why not something simpler since you have linq?
var dt = new DataTable();
var columnIndex = 0;
var columnName = "UserID";
var Dict = dt.AsEnumerable().ToDictionary( _
row => row(columnName), _
row => row(columnIndex));
It becomes even easier if you're working with strongly-typed datasets:
var dt = new dsData.UsersDataTable();
var Dict = dt.ToDictionary(dr => dr.UserName, dr => dr.UserID);