ListExpression

The ListExpression is part of the Dynamic Where feature; it represents the collection of WhereExpression objects.

Implementation

Example

Target SQL where clause:

WHERE City IN ('Chicago IL','Seattle WA', 'Portland OR')

WhereExpression where =
    new BinaryExpression(
        new FieldExpression("SALESMEN","City"),
        new ListExpression(
            new WhereExpression[]{ new ConstantExpression("Chicago IL",DataType.String),
                                   new ConstantExpression("Seattle WA", DataType.String),
                                   new ConstantExpression("Portland OR", DataType.String) }),
            BinaryOperator.In);

let whereExpression = BinaryExpression(
                        FieldExpression("SALESMEN", "City"),
                        ListExpression(
                            [
                                ConstantExpression("Chicago IL", DataType.String),
                                ConstantExpression("Seattle WA", DataType.String),
                                ConstantExpression("Portland OR", DataType.String)
              ]),
                        BinaryOperator.In)

WhereExpression where = new BinaryExpression(
        new FieldExpression("SALESMEN","City"),
        new ListExpression(
            new WhereExpression[]{ new ConstantExpression("Chicago IL",DataType.String),
                                   new ConstantExpression("Seattle WA", DataType.String),
                                   new ConstantExpression("Portland OR", DataType.String) }),
            BinaryOperator.In);

let whereExpression = BinaryExpression(
                        FieldExpression("SALESMEN", "City"),
                        ListExpression(
                            [
                                ConstantExpression("Chicago IL", DataType.String),
                                ConstantExpression("Seattle WA", DataType.String),
                                ConstantExpression("Portland OR", DataType.String)
              ]),
                        BinaryOperator.In)

with ClientDataModule.tbl_SALESMEN,DynamicWhere do begin
  Expression:=NewBinaryExpression(
                NewField(LogicalName,'City'), NewList(
               [NewConstant('Chicago IL',datString),
                NewConstant('Seattle WA',datString),
                NewConstant('Portland OR',datString)]),
               dboIn);
end;

myTable.dynamicWhere = new RemObjects.DataAbstract.DynamicWhere(
            new RemObjects.DataAbstract.BinaryExpression(
                new RemObjects.DataAbstract.FieldExpression("City"),
                new RemObjects.DataAbstract.ListExpression([
                    new RemObjects.DataAbstract.ConstantExpression("String", "Chicago IL", 0),
          new RemObjects.DataAbstract.ConstantExpression("String", "Seattle WA", 0)
                    new RemObjects.DataAbstract.ConstantExpression("String", "Portland OR", 0)
                ]), "In"
            )
        );

Generated XML

<?xml version="1.0"?>
<query xmlns="http://www.remobjects.com/schemas/dataabstract/queries/5.0" version="5.0">
  <where>
    <binaryoperation operator="In">
      <field tablename="SALESMEN">City</field>
      <list>
        <constant type="String" null="0">Chicago IL</constant>
        <constant type="String" null="0">Seattle WA</constant>
        <constant type="String" null="0">Portland OR</constant>
      </list>
    </binaryoperation>
   </where>
</query>