关于查找属性定义

Alice

TBizField中定义查找属性
  TBizField.LookupDef.Kind := TLookupKind.lkEnumValues;  //查找类型
  TBizField.LookupDef.ValidateKind   := TLookupValidateKind.vkMust; //查找值范围
  TBizField.LookupDef.SQL.Text       := ''; // 查找数据集的SQL 语句
  TBizField.LookupDef.KeyField       := 'KeyField'; //关键字段
  TBizField.LookupDef.DisplayField   := 'DisplayField'; //显示字段
  TBizField.LookupDef.DropDownButton := True; //是否显示下拉

Alice

还可以在代码中对这个查找属性的SQL语句赋值。
with TSQLDataSet(DataSetBroker1.DataSet) do
  begin
    Close;
    BizFieldByName('SZDW').LookDef.SQL.Text := 'SELECT DISTINCT T_WLDY.GYSBH, T_GYSXX.GYSMC, T_GYSXX.CZ  FROM T_WLDY,T_GYSXX where substring(T_WLDY.WLBH,1,1)='''+zhi+''' and T_WLDY.GYSBH=T_GYSXX.GYSBH ';
    Open;
  end;

Alice

定义一个数据集（DataSetLookupDataSet），把查找属性的关键值和显示值存到这个数据集里。然后执行如下代码：

var
  lBizField: TBizField;
  lStream: TMemoryStream;
begin
  lBizField := TBizDataSet(DataSetBrokerBZSJJ1.DataSet).FindBizField('SZ');
  if lBizField <> nil then
  begin
    lBizField.LookupDef.Kind := TLookupKind.lkEnumValues;
    lBizField.LookupDef.KeyField := 'ID';
    lBizField.LookupDef.DisplayField := 'XSMC';
    lStream := TMemoryStream.Create;
    try
      DataSetLookupDataSet.Open;
      DataSetLookupDataSet.SaveToStream(lStream, TDataPacketFormat.dfXML);
      lStream.Position := 0;
      lBizField.LookupDef.Values.LoadFromStream(lStream);
      TBizDataSet(DataSetBrokerBZSJJ1.DataSet).LayoutChange;
    finally
      lStream.Free;
    end;
  end
  else
    FindBizFieldError;
end;

Alice

取消查找的代码：
var
  lBizField: TBizField;
begin
  lBizField := TBizDataSet(DataSetBrokerBZSJJ1.DataSet).FindBizField('SZ');
  if lBizField <> nil then
  begin
    lBizField.LookupDef.Kind := TLookupKind.lkNone;
    TBizDataSet(DataSetBrokerBZSJJ1.DataSet).LayoutChange;
  end
  else
    FindBizFieldError;
end;