Auto Fill Field in Subform Of all the lines

Auto Fill Field in Subform Of all the lines

Hi, I fill in a subform, but fill all the data from it after that and add new rows.

With my code I can only fill in the first line and I do not want it to be "on add row".



if(input.Tipo_de_orden1  !=  null)
{
input.Registro_Mercancia.Tipo_de_orden1= input.Tipo_de_orden1;
}


Thanks