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어디가 잘못된건지 답변 부탁드립니다.

_______________     에러 내용      _______________

Short text
    The current statement requires a character-type data object.

What happened?
    Error in the ABAP Application Program

    The current ABAP program "SAPLKKBL" had to be terminated because it has
    come across a statement that unfortunately cannot be executed.

Error analysis
    At the statment
         "STRLEN( obj )..."
    , only character-type data objects are supported at the argument
    position "obj".

    In this particular case, the operand "obj" has the non-charcter-type type
    "I".

Trigger Location of Runtime Error
    Program                                 SAPLKKBL
    Include                                 LKKBLF99
    Row                                     3,908
    Module type                             (FORM)
    Module Name                             GEN_FIELD_OUT2

Source Code Extract

Line  SourceCde

 3878            using edit mask gs_fc-edit_mask.
 3879     if gs_fc-inttype ca 'NnIiPpBbSs'.  "Y7AK010240
 3880       condense gs_out-hlpchar.
 3881     endif.
 3882     gs_out-hlplen = strlen( gs_out-hlpchar ).
 3883 * Bei NUMC führende '0' und ' ' nicht berücksichtigen
 3884   elseif gs_fc-tech_form = 6.

 3887       condense gs_out-hlpchar.
 3888     endif.
 3889     gs_out-hlplen = strlen( gs_out-hlpchar ).
 3890   elseif gs_fc-tech_form = 11.                              "INS TECH11
 3891 *   Min. Ausgabelänge für ein Datum ist immer 8
 3892     if gs_fc-datatype = 'DATS'.                             "INS TECH11
 3893       gs_out-hlplen = 8.                                    "INS TECH11
 3894 *    Min. Ausgabelänge für eine Uhrzeit ist immer 6
 3895     elseif gs_fc-datatype = 'TIMS'.                         "INS TECH11
 3896       gs_out-hlplen = 6.                                    "INS TECH11
 3897     endif.                                                  "INS TECH11
 3898   elseif gs_fc-tech_form = 1 or gs_fc-tech_form = 90.
 3899 *   Überführung int. in ext. Format via Konvertierungsexit
 3900     if not gs_fc-convexit is initial or                     "INS TECH11
 3901        not gs_fc-inttype ca 'CN'.
 3902 *   elseif not gs_fc-convexit is initial.            "DEL TECH11
 3903       write <field> to gs_out-hlpchar left-justified.
 3904       gs_out-hlplen = strlen( gs_out-hlpchar ).
 3905 *   ansonsten entspricht sich min. Ausgabelänge und Ausprägungslänge
 3906     else.
 3907       if gs_fc-tech_form ne 99.
>>>>>         gs_out-hlplen = strlen( <field> ).
 3909       endif.
 3910     endif.
 3911   endif.
 3912 *   Falls Ausprägung abgeschnitten wird, dann wird noch ein weiterer
 3913 *   Charakter für die Visualisierung mittels Symbol reserviert
 3914   if gs_out-hlplen > gs_fc-outputlen.
 3915     if gs_fc-outputlen = 0.
 3916       gs_out-hlplen = 0.
 3917     else.
 3918       gs_fc-outputlen = gs_fc-outputlen - 1.
 3919       ">>Unicode/Doublebyte 1
 3920       get parameter id 'SLI' field g_sli.
 3921       if g_sli eq 'UNICODE' or g_sli eq 'MULTIBYTE' or
 3922       not cl_gui_alv_grid=>m_multibyte is initial.     "Y7AK013723
 3923         data:
 3924           im_pos_vis   type i,
 3925           im_pos_tech  type i,
 3926           ex_pos_vis   type i,
 3927           ex_pos_tech  type i,