I have a line of code that has been written using MoreLinq here :

var maxPage = _pageState?.Value?.Pages?.MaxBy(p => p.Type.Grids["desktop"].ColCount)?.FirstOrDefault();

Because my solution is using both MoreLinq and Linq I am getting the following error:

The call is ambiguous between the following methods or properties: 'MoreLinq.MoreEnumerable.DistinctBy<TSource, TKey>(System.Collections.Generic.IEnumerable, System.Func<TSource, TKey>)' and 'System.Linq.Enumerable.DistinctBy<TSource, TKey>(System.Collections.Generic.IEnumerable, System.Func<TSource, TKey>)

I have tried adding the following static extension to my document: MoreLinq.Extensions.AppendExtension but this errors out FirstOrDefault() at the end of the line with the following error:

'MyClass' does not contain a definition for 'FirstOrDefault' and no accessible extension method 'FirstOrDefault' accepting a first argument of type 'MyClass' could be found (are you missing a using directive or an assembly reference?)

I have tried also removing MoreLinq but I get the same does not contain a defition for FirstOrDefault Error.

What is the best way to solve this issue?

CodePudding user response：

MaxBy and DistinctBy methods were introduced in .NET 6 which will result in the aforementioned problem if you are using MoreLinq. If you don't need any MoreLinq methods just remove it or replace with using System.Linq; (if you are not using the global/implicit usings).

If you still need both you can use the trick with splitting imports on before and after namespace (though it can be a bit esoteric):

// ... common imports
using MoreLinq.Extensions;

namespace YourNameSpace;
{
    using System.Linq; // default LINQ methods will be preferred

    // ... code
}

Or use static imports for only needed methods (see @github):

using static MoreLinq.Extensions.BatchExtension; // import classes holding needed extensions