//根据查询表(包含主表和关联表)获取所有查询字段 public IEnumerable <FieldViewModel> GetFieldsBySelectedTable() { if (TableMain == null && JoinTables.IsEmpty()) { return(null); } return(Fields.Where(field => (JoinTables.IsNotEmpty() && JoinTables.Select(t => t.Table).Contains(field.tbname)) || (TableMain != null && field.tbname == TableMain.tbname))); }