C# – How to sort a list

c++linq

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 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.

Best Solution

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.

Related Solutions

C# – How to sort a dictionary by value

Use LINQ:

Dictionary<string, int> myDict = new Dictionary<string, int>();
myDict.Add("one", 1);
myDict.Add("four", 4);
myDict.Add("two", 2);
myDict.Add("three", 3);

var sortedDict = from entry in myDict orderby entry.Value ascending select entry;

This would also allow for great flexibility in that you can select the top 10, 20 10%, etc. Or if you are using your word frequency index for type-ahead, you could also include StartsWith clause as well.

C# – How to cast int to enum

From an int:

YourEnum foo = (YourEnum)yourInt;

From a string:

YourEnum foo = (YourEnum) Enum.Parse(typeof(YourEnum), yourString);

// The foo.ToString().Contains(",") check is necessary for enumerations marked with an [Flags] attribute
if (!Enum.IsDefined(typeof(YourEnum), foo) && !foo.ToString().Contains(","))
{
    throw new InvalidOperationException($"{yourString} is not an underlying value of the YourEnum enumeration.")
}

Update:

From number you can also

YourEnum foo = (YourEnum)Enum.ToObject(typeof(YourEnum) , yourInt);

Best Solution

Related Solutions

C# – How to sort a dictionary by value

C# – How to cast int to enum

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