How to use Not In datatable.select

问题

I have a DataTable (Ado.Net) with column 'Status'. This column holds the values (in each records)

['Red','Green','Blue','Yellow','White','OtherColors']

I want to select all the rows which status value not Red,Green,Blue

What the kind of filter expression to use to select data with my proposed criteria. So i want to achive some thing like we used in sql query ( WHERE Status NOT IN ('Red','Green','Blue')

NB:This project is running .NET 2.0 i cant use linq

回答1:

I have tested it, it works as desired:

DataRow[] filtered = tblStatus.Select("Status NOT IN ('Red','Green','Blue')");

The resulting DataRow[] contains only DataRows with OtherColors, Yellow and White.

If you could use LINQ i'd prefer that:

string[] excludeStatus = {"Red","Green","Blue"};
var filteredRows = tblStatus.AsEnumerable()
    .Where(row => !excludeStatus.Contains(row.Field<string>("Status")));

回答2:

Without Linq you can use the rowfilter of a DataView like this

public DataTable GetFilteredData(DataTable table, string[] filterValues)
{
    var dv = new DataView(table);
    var filter = string.join("','", filterValues);
    dv.RowFilter = "Status NOT IN ('" + filter + "')";
    return dv.ToTable();
}

回答3:

Supposing your datatable is part of a typed dataset you can use Linq to datasets, from which you could something like:

var records = 
      from record in datatable
      where !record.Status.Contains('Red','Green','Blue')
      select record;

Even if you don't have a typed dataset Linq to datasets is your answer. You would need to some casting, but not to difficult.

来源：https://stackoverflow.com/questions/26359719/how-to-use-not-in-datatable-select