How to sort a list<datarow>?
I have a datatable which I will convert to a list<datarow>
. How do I sort the list based on some datatable column? I think it's something like list = list.Sort(p=>p.Field() but I am 开发者_如何学运维not sure about the syntax.
I am interested in using LINQ heavily so I was wondering if I should convert the datatable to a strongly typed generic list and take it from there instead of using linq to datasets. The only reason I didn't do this now is for performance reason. The datatable consists of about 20,000 records.
I'd recommend you covert the dataset to a generic list and use linq to sort:
var collection =
from c in people
orderby c.Name ascending
select c;
return collection.ToList();
Where people is the generic List. There are other ways to sort using linq.
Are you always going to return 20k records? The way I understand it, there's more overhead with datatables/sets/rows than with generic lists due to all the built-in .NET functions and methods...but I might be wrong.
In general if you want to sort a List<T>
you could do something like
list.Sort((a, b) => String.Compare(a.StringValue, b.StringValue));
Obviously this example is sorting string values alphabetically, but you should get the idea of the syntax to use.
You could use something like:-
list.Sort((x,y) => (int)x[i] > (int)y[i] ? 1 : ((int)x[i] < (int)y[i] ? -1 : 0))
Where i
is the index of the column you want to compare. In the example above the i column contains integers. If it contained strings you could do something like
list.Sort((x,y) => string.Compare((string)x[i], (string)y[i]))
Note that the Sort
method sorts the list in place, it does not create a new list.
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