1、建立自定义函数
浮点数显示
FUNCTION conversion_exit_zsign_output.
*"----------------------------------------------------------------------
*"*"Local interface:
*" IMPORTING
*" REFERENCE(INPUT)
*" EXPORTING
*" REFERENCE(OUTPUT)
*"----------------------------------------------------------------------
DATA: output1(20) TYPE c,
output2(20),
outdatum TYPE p DECIMALS 6.
IF not input is initial.
outdatum = input.
IF input > 0.
WRITE outdatum TO output1 ."RIGHT-JUSTIFIED .
ELSE.
outdatum = outdatum * ( -1 ).
WRITE outdatum TO output1 ."RIGHT-JUSTIFIED.
CONCATENATE '-' output1 INTO output1.
ENDIF.
ELSE.
CLEAR output1.
ENDIF.
CONDENSE output1 NO-GAPS .
WRITE output1 TO output2 RIGHT-JUSTIFIED .
output = output2.
ENDFUNCTION.
2、设置ALV输出格式字段格式
clear ls_fcat.
ls_fcat-fieldname = 'DEC'.
ls_fcat-inttype = 'P'.
ls_fcat-intlen = 10.
ls_fcat-col_pos = l_lin.
ls_fcat-seltext_s = ls_fcat-fieldname.
ls_fcat-seltext_m = ls_fcat-fieldname.
ls_fcat-seltext_l = ls_fcat-fieldname.
ls_fcat-edit_mask = '==ZSIGN'.
append ls_fcat to ct_fcat.
3、调用函数就可达到负数符号前显的效果。
call function 'REUSE_ALV_GRID_DISPLAY'
exporting
it_fieldcat = lt_fcat
tables
t_outtab = gt_outtab
exceptions
program_error = 1
others = 2.
这种方式同样可以实现相对复杂的显示效果，如财务凭证中S表示借，H表示贷，我们在显示的时候要显示“借”或“贷”，也可以写一个类似的函数来实现。
http://blog.163.com/arhao_h/blog/static/125169020103191200252/