To Process the Result of the Execution of the BQL Statement

Select() returns the PXResultset<T0> object. The type parameter (T0) is set to the first table selected by the business query language (BQL) statement, and PXResultset<T0> is a collection of PXResult<T0> objects. You can iterate through the result set in a foreach loop and obtain either data access class (DAC) instances or PXResult<> instances. A PXResult<> instance represents a whole result set record and can be cast to any of the DAC types joined in the BQL statement.

To Get the Objects of the Primary DAC

In the foreach loop, cast each PXResult<T0> object in the collection to an object of the main DAC. The PXResult<T0> object is implicitly converted to the T0 class. In the following sample code, records are selected from the Document table.

// Result set records are implicitly cast to the Document DAC.
foreach(Document doc in SelectFrom<Document>.View.Select(this))
{
    ...
}

To Get the Objects of Joined DACs

In the foreach loop, cast each PXResult<T0> object in the collection to the needed PXResult<T0, T1, T2, ...> object, where T0, T1, T2, and other type parameters are joined DACs from the BQL statement. The PXResult<T0, T1, T2, ...> type must be specialized with the DACs of all joined tables.
Cast each PXResult<T0, T1, T2, ...> item to any of the listed types to get the object of this type.

The following sample code shows how to process the result set of a BQL statement joining two tables.

// The static Select() method is called to execute a BQL command.
PXResultset<OrderLine> result =
    SelectFrom<OrderLine>.InnerJoin<SalesOrder>.
        On<SalesOrder.orderNbr.IsEqual<OrderLine.orderNbr>>.View.Select(this);

// Iterating over the result set:
// PXResult should be specialized with the DACs of all joined tables
// to be able to cast to these DACs.
foreach(PXResult<OrderLine, SalesOrder> record in result)
{
    // Casting a result set record to the OrderLine DAC:
    OrderLine detail = (OrderLine)record;
    // Casting a result set record to the SalesOrder DAC:
    SalesOrder order = (SalesOrder)record;
    ...
}

Note: Starting C# 7.0, you can also deconstruct the result set as shown in the following code example.

(var line, var poLine, var _, var lotSerClass) = 
    (PXResult<POReceiptLine, POLine, InventoryItem, INLotSerClass>)
    SelectFrom<POReceiptLine>
    .LeftJoin<POLine>.On<POReceiptLine.FK.OrderLine>
    .LeftJoin<InventoryItem>.On<POReceiptLine.FK.InventoryItem>
    .LeftJoin<INLotSerClass>.On<InventoryItem.FK.LotSerClass>
    .Where<POReceiptLine.receiptType.IsEqual<@P.AsString>
        .And<POReceiptLine.receiptNbr.IsEqual<@P.AsString>>
        .And<POReceiptLine.lineNbr.IsEqual<@P.AsInt>>>
    .View.Select(Base, split.ReceiptType, split.ReceiptNbr, split.LineNbr);

This code example is equivalent to the following code.

var row = (PXResult<POReceiptLine, POLine, InventoryItem, INLotSerClass>)
    SelectFrom<POReceiptLine>
    .LeftJoin<POLine>.On<POReceiptLine.FK.OrderLine>
    .LeftJoin<InventoryItem>.On<POReceiptLine.FK.InventoryItem>
    .LeftJoin<INLotSerClass>.On<InventoryItem.FK.LotSerClass>
    .Where<POReceiptLine.receiptType.IsEqual<@P.AsString>
        .And<POReceiptLine.receiptNbr.IsEqual<@P.AsString>>
        .And<POReceiptLine.lineNbr.IsEqual<@P.AsInt>>>
    .View.Select(Base, split.ReceiptType, split.ReceiptNbr, split.LineNbr);
POReceiptLine line = row;
POLine poLine = row;
INLotSerClass lotSerClass = row;