MULTI-SELECT CONTROL LOOKUP AT FORM LEVEL

Recently, i worked on the customization of form in which there is a field which has a lookup at Form level.  This lookup must select multiple fields and must reflect on the form and table as well.

This is the code at control level i.e StringEdit

public boolean modified()
{
boolean ret;
int i,l;
str temp,id;
container a;
Mzk_UAEAddress mzk;

;

ret = super();
a = ctrl.getSelectedFieldValues();
l = conLen(a);

select * from mzk;
select forUpdate Purpose from mzk where mzk.RecId == Mzk_UAEAddress.RecId;
mzk.Purpose = " ";
ttsBegin;
for(i = 1; i <= l;i++)
{

temp = conPeek(a,i);

mzk.Purpose = mzk.Purpose + temp + ",";
mzk.update();

}
ttsCommit;
return ret;
}