linq find in which position is my object in List [duplicate]

问题

kriteriji is type of List<Kriteriji>

var doc = kriteriji.Where(k => k.Ean == txtEan.Text
                     && k.PredmetObravnave == acPredmetObravnave.Text
                     && k.Tse == txtTse.Text
                     && k.DejanskaKolicina == Convert.ToInt32(txtKolicina.Text)
                     && k.KratekNazEnoteMere == acKNEnotaMere.Text
                     && k.OznakaLokacije == acOznakaLokacije.Text
                     && k.OznakaZapore == txtZapora.Text
                     && k.SarzaDob == txtSarzaDobavitelja.Text
                     && k.Sarza == txtSarza.Text
                     && k.DatumVelOd == datumOd
                     && k.DatumVelDo == datumDo).FirstOrDefault();

Now when I get doc how can I know in which position in List<kriteriji> is? I need to now if is in first, second,...

回答1:

Use the IndexOf method:

kriteriji.IndexOf(doc);

回答2:

I think you could create a (index , value) keyvaluepaire object at first and then retrive it like

        var doc = kriteriji.Select((value, index) => new { index, value })
            .Where(k => k.value.Ean == txtEan.Text
                 && k.value.PredmetObravnave == acPredmetObravnave.Text
                 && k.value.Tse == txtTse.Text
                 && k.value.DejanskaKolicina == Convert.ToInt32(txtKolicina.Text)
                 && k.value.KratekNazEnoteMere == acKNEnotaMere.Text
                 && k.value.OznakaLokacije == acOznakaLokacije.Text
                 && k.value.OznakaZapore == txtZapora.Text
                 && k.value.SarzaDob == txtSarzaDobavitelja.Text
                 && k.value.Sarza == txtSarza.Text
                 && k.value.DatumVelOd == datumOd
                 && k.value.DatumVelDo == datumDo).FirstOrDefault();

then you could get the index like

Console.WriteLine(doc.index);

回答3:

You can use an overload for select that will take an index and a Kriteriji.

Here is the documentation.

Then you could select an anonymous object with an Index property and a Doc property. If you would use IndexOf this will cause another search throughout the list while you already have that data.

回答4:

Try this:

var position = kriteriji.IndexOf(doc);

回答5:

You can find out the index with:

kriteriji.IndexOf(doc.First());

来源：https://stackoverflow.com/questions/8209197/linq-find-in-which-position-is-my-object-in-list

标签

linq

position