Edit Method Example on table.

Edit Method on table methods:-

We have 2 methods which we used to access another table data in our form in which we don't have that table as data source.Those are display and edit methods.

Edit method example:

 Suppose take  2 tables  cartable and rental table

 cartable fields-->1)carid as edt and primary index
                           2)Milege as edt

Rental Table Fields-->1)Carid 
                                 2)Custid

steps:

make a relation between cartable and rental table (normal relation in rental table with carid)
create a find method in cartable as

public static cartable find(carid _carid )
{
 cartable car;
 ;
 select car where car.carid==_carid;
 return car;
}

now create an edit method in rental table to edit milege of carid in cartable ,the method looks like

edit milege editmilege(boolean set,milege value)
{
  cartable cartable;
  milege ret;
  ;
cartable=cartable::find(this.carid);

if(set)
{
cartable.selectForUpdate(true);
 ttsbegin;
 cartable.milege=value;
 cartable.update();
 ttscommit;
 return value;
}
else
{
 ret=cartable.milege;
}
return ret;

}

now to test this create a form with rental table as data source and create a grid in design .Drag this edit method into grid it creates a column mileage .

open form and change the milege value it reflects in cartable .this is possible in case of edit method .if we use display method we cannot have a chance to change value .