Case insensitive GroupBy()

[kKen94]

Is it possible adding IEqualityComparer to GroupBy()?

[StefH]

Technically this is possible, however, what problem will this solve? Can you provide an example / unit test?

[kKen94]

var distinctedRaw = itemsToGroup  
                .AsQueryable()  
                .GroupBy($"new({string.Join(",", keys)})", "it")  
                .Select("it.First()")  
                .ToDynamicList<T>();

I use GroupBy() to group same values by dynamic keys and get unique values to remove duplicates.
But if I don't apply UpperCase(), "STRing"and "strING" for GroupBy are not the same and when I go to save data on database, the latter (obviously) crashes

[StefH]

If you execute this query on a database (sql), then this does work fine.

In LinqPad:

string[] keys = new[] { "Text" };

var city = x.AsQueryable().Where(t => t.Text == "NewYork");
city.Dump();

var distinctedRaw = x
  .AsQueryable().Where(t => t.Text == "NewYork")
  .GroupBy($"new({string.Join(",", keys)})", "it")
  .Select("it.FirstOrDefault()");
  distinctedRaw.Dump();

[kKen94]

The problem is that i'm not querying db, i'm manipulating local array 😃

[StefH]

I see.
It's possible to fix this, however it requires a lot of code changes in the GroupBy methods.

[kKen94]

... and a lot of time I suppose. This issue is not urgent, at the moment I lowercasing all. It's a bad workaround, I know, but otherwise I wouldn't know how to do it

[JonathanMagnan]

Hello @kKen94 ,

The v1.1.2 has been released.

The GroupBy now supports the IEqualityComparer overload.

Best Regards,

Jon

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