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I have a DataTable with a Name column. I want to generate a collection of the unique names ordered alphabetically. The following query ignores the order by clause.

Code
var names =
    (from DataRow dr in dataTable.Rows
    orderby (string)dr["Name"]
    select (string)dr["Name"]).Distinct();

Why does the orderby not get enforced?

Answers

    A= 1
    Answer

    To make it more readable and maintainable, you can also split it up into multiple LINQ statements.

    1. First, select your data into a new list, let's call it x1, do a projection if desired
    2. Next, create a distinct list, from x1 into x2, using whatever distinction you require
    3. Finally, create an ordered list, from x2 into x3, sorting by whatever you desire
    A= 2
    Answer

    The problem is that the Distinct operator does not grant that it will maintain the original order of values.

    So your query will need to work like this

    Code
    var names = (from DataRow dr in dataTable.Rows
                 select (string)dr["Name"]).Distinct().OrderBy( name => name );

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