Get a field in the field set based on the name.
Note calling locate() many times on the same message is not optimal.
When processing multiple fields in a message, looping through by
index and comparing the name may be more efficient, eliminating
unnecessary string compares.

C# |
public virtual LBMSDMField locate( string name )

- name (String)
- The name of the field to be searched for.

the LBMSDMField or null