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Ordering data by more than one column in LINQ query

In this post I’ll show how you can apply ordering on the multiple columns in LINQ query.

If you know LINQ basics, you must be aware that with the help of .OrderBy(x => x.Columnname) in the LINQ query we can order data of the source collection.

So many of the novice developers use the same function twice as mentioned below and thinks that will do the ordering on the multiple columns.

var students = context.Students
                .OrderBy(x => x.Name)
                .OrderBy(x => x.ClassName);

But that is not the solution and LINQ query always does the order by the column you specified in the last OrderBy() method.

We can do order by on more than one columns using lambda expressions as well as in traditional LINQ query.

Mentioned below are two solutions to achieve using Lambda and traditional LINQ queries:

Using Lambda Expression:
Change above mentioned query to following to make it work:

var students = context.Students
                .OrderBy(x => x.Name)
                .ThenBy(x => x.ClassName);

One important thing to remember is always make use of ThenBy() after OrderBy()  because  OrderBy() returns an IOrderedEnumerable which then exposes the Methods: ThenBy() and ThenByDescending().

Using traditional LINQ Query:
If you are traditional LINQ query writer and don’t want to use the lambda expression, then you can do ordering on multiple columns with following way:

var students = from s in context.Students
                orderby s.Name, s.ClassName
                select s;

Hope that helps !!!

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