c# - DataTable filterExpression中如何使用EXISTS？

Question

我需要在 C#.net 中过滤 DataTable 我已经尝试过

string sortExpression="id ASC";
string filterExpression;
DataTable dt;
DataRow[] drA;
filterExpression = "exists (select distinct id from table_b b where a.id=b.id )";
drA = dtAdvancedSearched.Select(filterExpression, sortExpression);
dt = drA .CopyToDataTable();

但这会产生错误

谁能帮我使用 exists in .net

Answer 1

RowFilter syntax 中没有exists .

所以我建议使用 Linq-To-DataSet相反:

IEnumerable<DataRow> tableBRows = table_b.AsEnumerable();
DataTable dt = dtAdvancedSearched.AsEnumerable()
    .Where(row => tableBRows.Any(b => b.Field<int>("id") == row.Field<int>("id")))
    .OrderBy(row => row.Field<int>("id"))
    .CopyToDataTable();