将 ABAP 740 语法转换为 700 - VALUE & LOOP AT ... GROUP BY
Converting ABAP 740 syntax to 700 - VALUE & LOOP AT ... GROUP BY
我在网上找到了一个demo program我想用的tree salv，但由于它使用740语法，我必须先转换它。这也是进一步了解新语法的好机会。
我已经完成了几乎所有的工作，但是 VALUE 遇到了问题。阅读此 wiki entry 等内容对我没有帮助。
740中的原码：
" Treenodes einfügen
LOOP AT it_spfli ASSIGNING FIELD-SYMBOL(<c>) GROUP BY <c>-carrid.
DATA(it_cp) = VALUE ty_it_spfli( FOR <cp> IN GROUP <c> ( <cp> ) ).
DATA(o_parent) = o_tree->get_nodes( )->add_node( related_node = ''
relationship = cl_gui_column_tree=>relat_last_child
collapsed_icon = CONV #( icon_closed_folder )
expanded_icon = CONV #( icon_open_folder )
row_style = if_salv_c_tree_style=>intensified
text = CONV #( <c>-carrid ) ).
IF lines( it_cp ) > 1.
o_parent->get_item( 'CARRID' )->set_type( if_salv_c_item_type=>button ).
o_parent->get_item( 'CARRID' )->set_value( 'all' ).
ENDIF.
LOOP AT GROUP <c> ASSIGNING FIELD-SYMBOL(<f>).
DATA(o_carrid) = o_tree->get_nodes( )->add_node( related_node = o_parent->get_key( )
relationship = cl_gui_column_tree=>relat_last_child
data_row = <f>
row_style = if_salv_c_tree_style=>intensified
text = CONV #( <f>-connid ) ).
o_carrid->get_item( 'CARRID' )->set_type( if_salv_c_item_type=>checkbox ).
o_carrid->get_item( 'CARRID' )->set_editable( abap_true ).
ENDLOOP.
ENDLOOP.
700 中的新代码，除了符合 VALUE 的行：
" new variables added to convert code to 700
DATA: o_nodes TYPE REF TO cl_salv_nodes,
o_parent TYPE REF TO cl_salv_node,
o_carrid TYPE REF TO cl_salv_node,
o_item TYPE REF TO cl_salv_item,
o_key TYPE lvc_nkey.
DATA: h_collapsed_icon TYPE salv_de_tree_image VALUE 'icon_closed_folder',
h_expanded_icon TYPE salv_de_tree_image VALUE 'icon_open_folder',
h_text_carrid TYPE lvc_value.
DATA: it_cp TYPE STANDARD TABLE OF ty_it_spfli.
SORT it_spfli BY carrid.
" Treenodes einfügen
LOOP AT it_spfli ASSIGNING <c>.
AT NEW carrid.
it_cp = value TY_IT_SPFLI( for <CP> in GROUP <c> ( <CP> ) ). <--- Here
o_nodes = o_tree->get_nodes( ).
h_text_carrid = <c>-carrid.
o_parent = o_nodes->add_node( related_node = ''
relationship = cl_gui_column_tree=>relat_last_child
collapsed_icon = h_collapsed_icon
expanded_icon = h_expanded_icon
row_style = if_salv_c_tree_style=>intensified
text = h_text_carrid ).
IF LINES( it_cp ) > 1.
o_item = o_parent->get_item( 'CARRID' ).
o_item->set_type( if_salv_c_item_type=>button ).
o_item->set_value( 'all' ).
ENDIF.
ENDAT.
o_key = o_parent->get_key( ).
o_carrid = o_nodes->add_node( related_node = o_key
relationship = cl_gui_column_tree=>relat_last_child
data_row = <c>
row_style = if_salv_c_tree_style=>intensified
text = h_text_carrid ).
o_item = o_parent->get_item( 'CARRID' ).
o_item->set_type( if_salv_c_item_type=>checkbox ).
o_item->set_editable( abap_true ).
ENDLOOP.
我现在的问题是：
- 我是否使用
AT NEW 正确转换了 LOOP AT ... GROUP BY？
- 如何转换带有
VALUE 的行？
预先感谢您的帮助。
其实你问的是"FOR ... IN GROUP":
这一行是什么意思
TYPES: ty_it_spfli TYPE STANDARD TABLE OF spfli WITH DEFAULT KEY.
DATA it_spfli TYPE ty_it_spfli.
LOOP AT it_spfli ASSIGNING FIELD-SYMBOL(<c>) GROUP BY <c>-carrid.
DATA(it_cp) = VALUE ty_it_spfli( FOR <cp> IN GROUP <c> ( <cp> ) ).
...
ENDLOOP.
首先，带有 "GROUP BY" 的外循环迭代 CARRID 组件的不同值。比如内部的tableit_spfli可能有100行，但是只有10个不同的CARRID值，所以会迭代10次
里面的"value construction"FOR <cp> IN GROUP <c>在"group""members"处做了一个循环 of lines <c>，其中"members"是对应当前组的it_spfli行（对应当前组CARRID值的那些行），并且在每次迭代中，行 ( <cp> ) 附加到变量 it_cp.
这一行：
DATA(it_cp) = VALUE ty_it_spfli( FOR <cp> IN GROUP <c> ( <cp> ) ).
等价于LOOP AT GROUP下面的语法，也是从7.40开始有效，不过大家应该更清楚，7.0可以更直观的转换一下：
DATA(it_cp) = VALUE ty_it_spfli( ). " initialization (empty internal table)
LOOP AT GROUP <c> ASSIGNING FIELD-SYMBOL(<cp>).
INSERT <cp> INTO TABLE it_cp.
ENDLOOP.
您不能像您那样进行转换。 CARRID 原始代码分组的外层循环与 AT NEW 并不完全相同，因为它生成了一个临时组 table 然后你可以在任何地方使用。没有它，你应该提前生成组。
我没有验证代码，但是为了模拟 GROUP BY 然后使其余的转换变得容易而不必重写太多，我会为每个 CARRID 创建一个嵌套的 table原文：
DATA: BEGIN OF ls_spfli_carrid_group,
carrid TYPE carrid,
flights TYPE ty_it_spfli,
END OF ls_spfli_carrid_group,
lt_spfli_carrid_group LIKE STANDARD TABLE OF ls_spfli_carrid_group.
SORT it_spfli BY carrid.
LOOP AT it_spfli INTO ls_spfli.
AT NEW carrid.
it_spfli
ls_spfli_carrid_group-carrid = ls_spfli-carrid.
REFRESH ls_spfli_carrid_group-flights.
APPEND ls_spfli_carrid_group TO lt_spfli_carrid_group.
ENDAT.
APPEND ls_spfli TO ls_spfli_carrid_group-flights.
ENDLOOP.
LOOP AT lt_spfli_carrid_group INTO ls_spfli_carrid_group.
it_cp = ls_spfli_carrid_group-flights.
...
LOOP AT ls_spfli_carrid_group-flights INTO ls_flight. "Should be like the LOOP AT GROUP
ENDLOOP.
ENDLOOP.
感谢 Sandra 和 RaTiO 的帮助。
现在我明白了应该发生什么，我有以下两个解决方案（其中一个是来自 RaTiO 的解决方案）。
（应该发生什么：VALUE 命令应该用循环 table 的那些行填充另一个 itab，其中包含当前 CARRID。然后取决于数量行，你可以看到节点是否有子节点，因此需要是一个扩展按钮。）
所以我自己想到的解决办法是在LOOP里面填充一份table，删除那些不包含当前CARRID的条目。
DATA: it_copy_spfli TYPE ty_it_spfli.
...
SORT it_spfli BY carrid.
LOOP AT it_spfli ASSIGNING <c>.
AT NEW carrid.
REFRESH it_copy_spfli.
it_copy_spfli = it_spfli.
DELETE it_copy_spfli WHERE carrid <> <c>-carrid.
...
IF LINES( it_copy_spfli ) > 1.
...
ENDIF.
ENDAT.
...
ENDLOOP.
然后是 RaTiO 的解决方案，创建一个嵌套的 table 来代替循环。
DATA: it_copy_spfli TYPE ty_it_spfli.
DATA: BEGIN OF ls_spfli_carrid_group,
carrid TYPE s_carr_id,
flights TYPE ty_it_spfli,
END OF ls_spfli_carrid_group.
DATA: ls_spfli TYPE spfli,
ls_flight TYPE spfli,
lt_spfli_carrid_group LIKE STANDARD TABLE OF ls_spfli_carrid_group.
SORT it_spfli BY carrid.
LOOP AT it_spfli INTO ls_spfli.
APPEND ls_spfli TO ls_spfli_carrid_group-flights.
AT END OF carrid.
ls_spfli_carrid_group-carrid = ls_spfli-carrid.
APPEND ls_spfli_carrid_group TO lt_spfli_carrid_group.
REFRESH ls_spfli_carrid_group-flights.
ENDAT.
ENDLOOP.
LOOP AT lt_spfli_carrid_group INTO ls_spfli_carrid_group.
REFRESH it_copy_spfli.
it_copy_spfli = ls_spfli_carrid_group-flights.
...
h_text_carrid = ls_spfli_carrid_group-carrid.
...
IF LINES( it_copy_spfli ) > 1.
...
ENDIF.
LOOP AT ls_spfli_carrid_group-flights INTO ls_flight.
...
o_carrid = o_nodes->add_node( ...
data_row = ls_flight
... ).
...
ENDLOOP.
ENDLOOP.
然后我将其修改为使用 FIELD-SYMBOLS。
DATA: it_copy_spfli TYPE ty_it_spfli.
TYPES: BEGIN OF ty_spfli_carrid_group,
carrid TYPE s_carr_id,
flights TYPE ty_it_spfli,
END OF ty_spfli_carrid_group.
DATA: lt_spfli_carrid_group TYPE STANDARD TABLE OF ty_spfli_carrid_group.
FIELD-SYMBOLS: <spfli> TYPE spfli,
<flight> TYPE spfli,
<spfli_carrid_group> TYPE ty_spfli_carrid_group.
SORT it_spfli BY carrid.
LOOP AT it_spfli ASSIGNING <spfli>.
AT NEW carrid.
APPEND INITIAL LINE TO lt_spfli_carrid_group ASSIGNING <spfli_carrid_group>.
ENDAT.
APPEND <spfli> TO <spfli_carrid_group>-flights.
AT END OF carrid.
<spfli_carrid_group>-carrid = <spfli>-carrid.
ENDAT.
ENDLOOP.
LOOP AT lt_spfli_carrid_group ASSIGNING <spfli_carrid_group>.
...
LOOP AT <spfli_carrid_group>-flights ASSIGNING <flight>.
...
ENDLOOP.
ENDLOOP.
所有解决方案都按预期工作。比较运行时，最后一个是最快的，但它们非常接近。所以我决定使用我的，因为它只有几行，而 RaTiO 需要另一个 LOOP。
再次感谢您=)
我在网上找到了一个demo program我想用的tree salv，但由于它使用740语法，我必须先转换它。这也是进一步了解新语法的好机会。
我已经完成了几乎所有的工作，但是 VALUE 遇到了问题。阅读此 wiki entry 等内容对我没有帮助。
740中的原码：
" Treenodes einfügen
LOOP AT it_spfli ASSIGNING FIELD-SYMBOL(<c>) GROUP BY <c>-carrid.
DATA(it_cp) = VALUE ty_it_spfli( FOR <cp> IN GROUP <c> ( <cp> ) ).
DATA(o_parent) = o_tree->get_nodes( )->add_node( related_node = ''
relationship = cl_gui_column_tree=>relat_last_child
collapsed_icon = CONV #( icon_closed_folder )
expanded_icon = CONV #( icon_open_folder )
row_style = if_salv_c_tree_style=>intensified
text = CONV #( <c>-carrid ) ).
IF lines( it_cp ) > 1.
o_parent->get_item( 'CARRID' )->set_type( if_salv_c_item_type=>button ).
o_parent->get_item( 'CARRID' )->set_value( 'all' ).
ENDIF.
LOOP AT GROUP <c> ASSIGNING FIELD-SYMBOL(<f>).
DATA(o_carrid) = o_tree->get_nodes( )->add_node( related_node = o_parent->get_key( )
relationship = cl_gui_column_tree=>relat_last_child
data_row = <f>
row_style = if_salv_c_tree_style=>intensified
text = CONV #( <f>-connid ) ).
o_carrid->get_item( 'CARRID' )->set_type( if_salv_c_item_type=>checkbox ).
o_carrid->get_item( 'CARRID' )->set_editable( abap_true ).
ENDLOOP.
ENDLOOP.
700 中的新代码，除了符合 VALUE 的行：
" new variables added to convert code to 700
DATA: o_nodes TYPE REF TO cl_salv_nodes,
o_parent TYPE REF TO cl_salv_node,
o_carrid TYPE REF TO cl_salv_node,
o_item TYPE REF TO cl_salv_item,
o_key TYPE lvc_nkey.
DATA: h_collapsed_icon TYPE salv_de_tree_image VALUE 'icon_closed_folder',
h_expanded_icon TYPE salv_de_tree_image VALUE 'icon_open_folder',
h_text_carrid TYPE lvc_value.
DATA: it_cp TYPE STANDARD TABLE OF ty_it_spfli.
SORT it_spfli BY carrid.
" Treenodes einfügen
LOOP AT it_spfli ASSIGNING <c>.
AT NEW carrid.
it_cp = value TY_IT_SPFLI( for <CP> in GROUP <c> ( <CP> ) ). <--- Here
o_nodes = o_tree->get_nodes( ).
h_text_carrid = <c>-carrid.
o_parent = o_nodes->add_node( related_node = ''
relationship = cl_gui_column_tree=>relat_last_child
collapsed_icon = h_collapsed_icon
expanded_icon = h_expanded_icon
row_style = if_salv_c_tree_style=>intensified
text = h_text_carrid ).
IF LINES( it_cp ) > 1.
o_item = o_parent->get_item( 'CARRID' ).
o_item->set_type( if_salv_c_item_type=>button ).
o_item->set_value( 'all' ).
ENDIF.
ENDAT.
o_key = o_parent->get_key( ).
o_carrid = o_nodes->add_node( related_node = o_key
relationship = cl_gui_column_tree=>relat_last_child
data_row = <c>
row_style = if_salv_c_tree_style=>intensified
text = h_text_carrid ).
o_item = o_parent->get_item( 'CARRID' ).
o_item->set_type( if_salv_c_item_type=>checkbox ).
o_item->set_editable( abap_true ).
ENDLOOP.
我现在的问题是：
- 我是否使用
AT NEW正确转换了LOOP AT ... GROUP BY？ - 如何转换带有
VALUE的行？
预先感谢您的帮助。
其实你问的是"FOR ... IN GROUP":
这一行是什么意思TYPES: ty_it_spfli TYPE STANDARD TABLE OF spfli WITH DEFAULT KEY.
DATA it_spfli TYPE ty_it_spfli.
LOOP AT it_spfli ASSIGNING FIELD-SYMBOL(<c>) GROUP BY <c>-carrid.
DATA(it_cp) = VALUE ty_it_spfli( FOR <cp> IN GROUP <c> ( <cp> ) ).
...
ENDLOOP.
首先，带有 "GROUP BY" 的外循环迭代 CARRID 组件的不同值。比如内部的tableit_spfli可能有100行，但是只有10个不同的CARRID值，所以会迭代10次
里面的"value construction"FOR <cp> IN GROUP <c>在"group""members"处做了一个循环 of lines <c>，其中"members"是对应当前组的it_spfli行（对应当前组CARRID值的那些行），并且在每次迭代中，行 ( <cp> ) 附加到变量 it_cp.
这一行：
DATA(it_cp) = VALUE ty_it_spfli( FOR <cp> IN GROUP <c> ( <cp> ) ).
等价于LOOP AT GROUP下面的语法，也是从7.40开始有效，不过大家应该更清楚，7.0可以更直观的转换一下：
DATA(it_cp) = VALUE ty_it_spfli( ). " initialization (empty internal table)
LOOP AT GROUP <c> ASSIGNING FIELD-SYMBOL(<cp>).
INSERT <cp> INTO TABLE it_cp.
ENDLOOP.
您不能像您那样进行转换。 CARRID 原始代码分组的外层循环与 AT NEW 并不完全相同，因为它生成了一个临时组 table 然后你可以在任何地方使用。没有它，你应该提前生成组。
我没有验证代码，但是为了模拟 GROUP BY 然后使其余的转换变得容易而不必重写太多，我会为每个 CARRID 创建一个嵌套的 table原文：
DATA: BEGIN OF ls_spfli_carrid_group,
carrid TYPE carrid,
flights TYPE ty_it_spfli,
END OF ls_spfli_carrid_group,
lt_spfli_carrid_group LIKE STANDARD TABLE OF ls_spfli_carrid_group.
SORT it_spfli BY carrid.
LOOP AT it_spfli INTO ls_spfli.
AT NEW carrid.
it_spfli
ls_spfli_carrid_group-carrid = ls_spfli-carrid.
REFRESH ls_spfli_carrid_group-flights.
APPEND ls_spfli_carrid_group TO lt_spfli_carrid_group.
ENDAT.
APPEND ls_spfli TO ls_spfli_carrid_group-flights.
ENDLOOP.
LOOP AT lt_spfli_carrid_group INTO ls_spfli_carrid_group.
it_cp = ls_spfli_carrid_group-flights.
...
LOOP AT ls_spfli_carrid_group-flights INTO ls_flight. "Should be like the LOOP AT GROUP
ENDLOOP.
ENDLOOP.
感谢 Sandra 和 RaTiO 的帮助。
现在我明白了应该发生什么，我有以下两个解决方案（其中一个是来自 RaTiO 的解决方案）。
（应该发生什么：VALUE 命令应该用循环 table 的那些行填充另一个 itab，其中包含当前 CARRID。然后取决于数量行，你可以看到节点是否有子节点，因此需要是一个扩展按钮。）
所以我自己想到的解决办法是在LOOP里面填充一份table，删除那些不包含当前CARRID的条目。
DATA: it_copy_spfli TYPE ty_it_spfli.
...
SORT it_spfli BY carrid.
LOOP AT it_spfli ASSIGNING <c>.
AT NEW carrid.
REFRESH it_copy_spfli.
it_copy_spfli = it_spfli.
DELETE it_copy_spfli WHERE carrid <> <c>-carrid.
...
IF LINES( it_copy_spfli ) > 1.
...
ENDIF.
ENDAT.
...
ENDLOOP.
然后是 RaTiO 的解决方案，创建一个嵌套的 table 来代替循环。
DATA: it_copy_spfli TYPE ty_it_spfli.
DATA: BEGIN OF ls_spfli_carrid_group,
carrid TYPE s_carr_id,
flights TYPE ty_it_spfli,
END OF ls_spfli_carrid_group.
DATA: ls_spfli TYPE spfli,
ls_flight TYPE spfli,
lt_spfli_carrid_group LIKE STANDARD TABLE OF ls_spfli_carrid_group.
SORT it_spfli BY carrid.
LOOP AT it_spfli INTO ls_spfli.
APPEND ls_spfli TO ls_spfli_carrid_group-flights.
AT END OF carrid.
ls_spfli_carrid_group-carrid = ls_spfli-carrid.
APPEND ls_spfli_carrid_group TO lt_spfli_carrid_group.
REFRESH ls_spfli_carrid_group-flights.
ENDAT.
ENDLOOP.
LOOP AT lt_spfli_carrid_group INTO ls_spfli_carrid_group.
REFRESH it_copy_spfli.
it_copy_spfli = ls_spfli_carrid_group-flights.
...
h_text_carrid = ls_spfli_carrid_group-carrid.
...
IF LINES( it_copy_spfli ) > 1.
...
ENDIF.
LOOP AT ls_spfli_carrid_group-flights INTO ls_flight.
...
o_carrid = o_nodes->add_node( ...
data_row = ls_flight
... ).
...
ENDLOOP.
ENDLOOP.
然后我将其修改为使用 FIELD-SYMBOLS。
DATA: it_copy_spfli TYPE ty_it_spfli.
TYPES: BEGIN OF ty_spfli_carrid_group,
carrid TYPE s_carr_id,
flights TYPE ty_it_spfli,
END OF ty_spfli_carrid_group.
DATA: lt_spfli_carrid_group TYPE STANDARD TABLE OF ty_spfli_carrid_group.
FIELD-SYMBOLS: <spfli> TYPE spfli,
<flight> TYPE spfli,
<spfli_carrid_group> TYPE ty_spfli_carrid_group.
SORT it_spfli BY carrid.
LOOP AT it_spfli ASSIGNING <spfli>.
AT NEW carrid.
APPEND INITIAL LINE TO lt_spfli_carrid_group ASSIGNING <spfli_carrid_group>.
ENDAT.
APPEND <spfli> TO <spfli_carrid_group>-flights.
AT END OF carrid.
<spfli_carrid_group>-carrid = <spfli>-carrid.
ENDAT.
ENDLOOP.
LOOP AT lt_spfli_carrid_group ASSIGNING <spfli_carrid_group>.
...
LOOP AT <spfli_carrid_group>-flights ASSIGNING <flight>.
...
ENDLOOP.
ENDLOOP.
所有解决方案都按预期工作。比较运行时，最后一个是最快的，但它们非常接近。所以我决定使用我的，因为它只有几行，而 RaTiO 需要另一个 LOOP。
再次感谢您=)