Exporting Tables from BSP to Class Methods

Question

Afternoon Everybody,
in true SAP OSS Message style I post this question on it's own thread to enable maximum value from the reward points.
Question:
I have a BSP, in an event in my BSP I call a method in my class.
I have mastered Exporting parameters to the methods from the BSP and Importing parameters back to the BSP from the methods, but now, I need so Export a table to the method and I don't know how to.
Also, in combination with this, when I create the method I am able to setup the importing parameters, but how can create/define the importing table ?
If this is not clear I will add more info.
Thanks for your help,
Tomas.

Answer 1

Tomas,
The key to problem is always to learn a few "nice" things defined in the system. So let me see. The first problem you have is that methods are declared of the form:
method <parm> <direction> TYPE [REF TO] <t>
parm = the name of the paramter
direction = IMPORTING|EXPORTING|CHANGING|RETURNING
t = type of parm
However, in this type it is not possible to write that you want "type of table". You can only use predefined types (either internal or indictionary).
Having said this, most people with extensive ABAP experience before the OO-wave, tend to use character types all the time. However, we nearly always use only type string. And exactly for this type there is a type string_table.
So the code would be:
<u>Declaration:</u>
  method lines changing type string_table
<u>Calling:</u>
  DATA: t TYPE string_table.
  APPEND 'Hello' TO t.
  APPEND 'World' TO t.
  class=>method( CHANGING lines = t ).
<u>Method Implementation:</u>
  DATA: line LIKE LINE OF lines.
  LOOP AT lines INTO line.
    TRANSLATE line TO UPPER CASE.
    MODIFY lines FROM line. " write back
  ENDLOOP.
<u>Better Method Implementation (works directly on row):</u>
  FIELD-SYMBOLS: <line> LIKE LINE OF lines.
  LOOP AT lines ASSIGNING <line>.
    TRANSLATE <line> TO UPPER CASE.
  ENDLOOP.
These two types <b>string</b> and <b>string_table</b> goes a long way. The other two types that I often use are <b>ihttpvnp</b> and <b>Tihttpvnp</b> (table): they are good for name/value pairs of strings.
Now is the time that you should invest 30 minutes reading each time that you run into a problem. You have the framework, just check up on one aspect each time. (I usually use online help, for example to understand MODIFY for writing this text.)