This is a simple way to add a custom form lookup to a new field with x++ code. This example is done with a test table named FO_TestTable that has the three fields “TestField1”, “TestField2” and “TestField3”. The table FO_TestTable has an index named “TestIdx”.
I have added a field on the table CustTable named TestField1. On this field that now can be found on CustTable form on the CustTable datasource node, I have added the “Override method” “lookup”.
Below you can see how I have edited the method lookup to fit my needs. Notice that the sysTableLookup is based on an ordinary query, this means that you can manipulate this query as you see fit.