SAP 动态内表demo—-自用详解编程语言

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*& Report Z_TEST 
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REPORT Z_TEST. 
FIELD-SYMBOLS: <dyn_table> TYPE STANDARD TABLE, 
              <dyn_wa>, 
              <dyn_field>. 
DATA: dy_table TYPE REF TO data, 
     dy_line  TYPE REF TO data, 
     it_structure TYPE lvc_t_fcat, 
     wa_structure TYPE lvc_s_fcat. 
START-OF-SELECTION. 
 PERFORM create_structure.  " 定义内表的结构 
 
 PERFORM create_dynamic_table.  " 按照定义的内表结构，产生一个内表 
 
 PERFORM write_data_to_dyntable.  " 向动态内表中写数 
 
 PERFORM output_dyntable_data.   " 从动态内表中取数，并写到屏幕 
 
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*&      Form  create_structure 
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FORM create_structure . 
 wa_structure-fieldname = 'COL1'.  " 第一列列名 
 wa_structure-col_pos   = 1.       " 表示第一列 --- 可心省略，默认情况下，第一行对应到生产内表的第一列，如果指定，则按指定的列顺序生成内表 
 wa_structure-inttype = 'C'.       " 数据类型 
 wa_structure-intlen = 6.          " 长度 
 APPEND wa_structure TO it_structure. 
 
 wa_structure-fieldname = 'COL2'.  " 第二列列名 
 wa_structure-col_pos   = 2.       " 表示第二列--- 可心省略，默认情况下，第一行对应到生产内表的第一列，如果指定，则按指定的列顺序生成内表 
 wa_structure-inttype = 'C'.       " 数据类型 
 wa_structure-intlen = 6.          " 长度 
 APPEND wa_structure TO it_structure. 
 
 wa_structure-fieldname = 'COL3'.  " 第三列名 
 wa_structure-col_pos   = 3.       " 表示第三列 --- 可心省略，默认情况下，第一行对应到生产内表的第一列，如果指定，则按指定的列顺序生成内表 
 wa_structure-inttype = 'C'.       " 数据类型 
 wa_structure-intlen = 6.          " 长度 
 APPEND wa_structure TO it_structure. 
ENDFORM.                    " create_structure 
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*&      Form  create_dynamic_table 
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FORM create_dynamic_table . 
 
 CALL METHOD cl_alv_table_create=>create_dynamic_table 
   EXPORTING 
     it_fieldcatalog = it_structure 
   IMPORTING 
     ep_table        = dy_table. 
 
 ASSIGN dy_table->* TO <dyn_table>.    " 用表类型指针 <dyn_table> 指向 数据对象的内容. 
ENDFORM.                    " create_dynamic_table 
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*&      Form  write_data_to_dyntable 
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FORM write_data_to_dyntable . 
 DATA:wa_new_line TYPE REF TO data. 
 DATA:i TYPE n. 
 DATA:j TYPE n. 
 CREATE DATA wa_new_line LIKE LINE OF <dyn_table>.  " 建立一个与动态内表结构相同的数据对象，且数据对象为是一个结构 
 ASSIGN wa_new_line->* TO <dyn_wa>. 
 
 " 用<dyn_wa>指针指向该结构 
 DO 3 TIMES. 
   i = i + 1. 
   CLEAR j. 
   LOOP AT it_structure INTO wa_structure. 
     j = j + 1. 
     ASSIGN COMPONENT wa_structure-fieldname OF STRUCTURE <dyn_wa> TO <dyn_field>.  " 用指针 <dyn_field>指向工作区<dyn_wa>中的一个字段，字段名为wa_structure-fieldname. 
     CONCATENATE i j INTO <dyn_field>.                                              " 给指针指向的字段赋值 
   ENDLOOP. 
   APPEND <dyn_wa> TO <dyn_table>. 
 ENDDO. 
ENDFORM.                    " write_data_to_dyntable 
 
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*&      Form  output_dyntable_data 
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FORM output_dyntable_data . 
 LOOP AT it_structure INTO wa_structure. 
   WRITE: wa_structure-fieldname(5). 
 ENDLOOP. 
 LOOP AT <dyn_table> INTO <dyn_wa>. 
   WRITE: / . 
   LOOP AT it_structure INTO wa_structure. 
     ASSIGN COMPONENT wa_structure-fieldname OF STRUCTURE <dyn_wa> TO <dyn_field>.  " 用指针 <dyn_field>指向工作区<dyn_wa>中的一个字段，字段名为wa_structure-fieldname. 
     WRITE: <dyn_field>. 
   ENDLOOP. 
 ENDLOOP. 
ENDFORM.                    " output_dyntable_data