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USEREXIT
Userxits allow us to add our own functionality to SAP standard program
without modifying it .
These are implemented in the form of subroutines and hence are also known as
FORM EXITs. The userexits are generally collected in includes and attached to
the standard program by the SAP.
All
Userexits start with the word USEREXIT_...
FORM USEREXIT_..
z..
ENDFORM.
The problem lies in finding
the correct userexit and how to find it if one exists for the purpose. Once
the correct userexit is found the necessary
customer code is inserted in
the customer include starting with the z..
in the form routine.
e.g.
USEREXIT_SAVE_DOCUMENT_PREPARE
Certain application like SD
still provide this form of enhancement using userexit but this practice is no
longer being followed for newer extensions
instead they are using EXITs
which come bundeled in enhancement packages . Neverthiless existing USEREXITS
will be supported by SAP an all the newer versions of SAP.
HOW TO FIND USEREXITS
Userexits can be found in number of ways:
1) To find userexits in SD
module , goto object navigator(SE80) and select
development class from the list and enter VMOD in it. All of the userexits in
SD are contained in the development class VMOD. Press
enter and you will find all
the includes which contain userexits in SD for
different functions like
PRICING, ORDER PROCESSING etc. Select the userexit according to the
requirement and read the comment inserted in it
and start coding .
Some examples of userexits in
SD(SALES & DISTRIBUTION ) are:
1)ADDING OF NEW FIELDS IN
PRICING
In Pricing in SD the
fields on the basis of which pricing is done are derived from the FIELD
CATALOG which is a structure KOMG .This structure is used to transfer
transaction data to the pricing procedure in SD and is also known as
communication structure.This structure KOMG consists of two tables KOMK for
Header related fields and KOMP for item related fields.
The fields which
are not in either of the two tables KOMK and KOMP
cannot be used in pricing
.Sometimes a need arises when the pricing
is to be based on some other
criteria which is not present in the form of fields in either of the two
tables.
This problem can be
solved by using USEREXITS which are provided for pricing in SD.
Pricing takes
place both when the SALES ORDER ( Transaction VA01) is created as well as
when INVOICING ( Transaction VF01) is done.Hence SAP provides 2 userexits
,one for sales order processing which is
USEREXIT_PRICING_PREPARE_TKOMP
or
USEREXIT_PRICING_PREPARE_TKOMK
Depending upon which table (KOMK
or KOMP) the new fields were inserted we use either of the above two
userexits.These userexits are found in include MV45AFZZ of the standard SAP
sales order creation program SAPMV45A.
In the case of userexit which
will be called when invoicing is done ,these
are provided in the include
RY60AFZZ which is in the standard SAP
program SAPMV45A. The name of
the userexits are same. i.e
USEREXIT_PRICING_PREPARE_TKOMP
or
USEREXIT_PRICING_PREPARE_TKOMK
These userexits are used for
passing the data from the communication structure to the pricing procedure,
for this we have to fill the newely
created field in the
communication structure KOMG for this we fill the code in the above userexit
using the MOVE statement after the data that
has to be passed is taken
from the database table by using the SELECT statement. The actual structure
which is visible in these userexits and which is to be filled for that
particular field is TKOMP or TKOMK.
Before the coding for these
userexits is done ,it is necessary to create a new field in either of the two
tables KOMK or KOMP .For this purpose
includes are provided in each
of them .
To create the field in
header data(KOMK) the include provided is KOMKAZ
and to create the field
in item data(KOMP) the include provided is KOMPAZ.
One possible example for the
need of creating new fields can be e.g. Frieght to be based upon
transportation zone ,for this no field is available in field catalog and hence
it can be created in KOMK and then above userexits can be used to fill the
transportation data to it.
2)The other method of finding
userexit is to find the word USEREXIT in the
associated program of the
transaction for which we want to determine userexit using SE38.
3)The other method of finding
userexits is to find the include in case of SD/MM applications where the
userexits are located ,this can be found in the SAP reference IMG generally in
the subfolder under SYSTEM MODIFICATION.
Some other examples of
userexits in SD are:
USEREXIT_NUMBER_RANGE
This userexit is used to
assign a different internal document number to the
sales order(VA01) when it is
created depending on some criteria like a different SALES ORGANIZAION(VKORG) .
USEREXIT_SAVE_DOCUMENT_PREPARE
This userexit is used
to insert the ABAP code which will be called when
the document (sales order
VA01) is just about to be saved.This userexit is used generally for custom
checks on different fields , to display some information before the order will
be saved or for making changes to certain fields before the sales order will
be saved.
Exits &
Enhancements
There
are mainly six types of EXITs in sap which have been collected in the form of
enhancement packages and attached to standard code in SAP.
These are different from
USEREXIT in the way that they are implemented
in the form of FUNCTIONs
while in USEREXITS we use form routines for their implementation. These are
also sometimes known as function exits .
These start from
the word EXIT_ followed by the program name and then followed by a three digit
number.
e.g.
EXIT_SAPMV45A_002
This exit is found in SD in enhancement V45A0002.
TYPES OF EXITS
1)MENU EXITS
2)FUNCTION EXITS
3)TABLE EXITS
4)SCREEN EXITS
5)KEYWORD EXITS
6)FIELD EXITS
We use SAP transactions CMOD
and SMOD to manage exits. Before implementing an exit , it is required to
create the project by using CMOD
selecting the enhancement
e.g. V45A0002 and selecting the component
(one which fulfills our need)
i.e the exit which will be implemented in SMOD and after coding has been done
the project has to be activated.
An exit can be coded
only once.
FUNCTION EXITS
These are used to add functionality through ABAP code . These start from the
word EXIT_programname_NNN ending in a 3 digit number. No access code is
required to implement any tupe of exit including function exits.
The function
exits are called from the standard SAP program in the form
of ABAP statement
CALL CUSTOMER-FUNCTION 'NNN'
This is in contrast to
USEREXITs where PERFORM statement is used to call
the required userexit.
To implement the
FUNCTION EXITs first of all the project is created and a suitable enhancement
package is selected and from its compnents the function exit to be implemented
is selected and on double clicking it the exit code will appear in ABAP
EDITOR(se38) where a Z include will be found and the customer code should be
entered in this include.
e.g.
ADDING A DEFAULT
SOLD-TO-PARTY in Sales Order Creation
To show a default sold-to-party in this field when the user creates a sales
order (VA01) we can use a function exit .This function exit is located
in enhancement no V45A0002 .
Before we can choose the exit we have to
create a project in CMOD
after that enter V45A0002 in the enhancement field and click on the components
. In the components you will see the
exit EXIT_SAPMV45A_002 . This
exit is used for our purpose.
Double clicking on
this exit will takes us to function builder (SE37) . This
function exit has one
exporting parameters and two importing parameters, we are interested in
exporting parameter which is E_KUNNR
of type KNA1-KUNNR i.e if we
move the desired customer name to this
structure(E_KUNNR) it will be
shown in the field as the default value when we create the sales order.
This function also
contains a customer include ZXVVA04 . This include
will be used to write our
custom code .
Double clicking on this include and it will prompt us that this include does
not exists do you want to create this object ,select yes and the include will
be created .In this include we can write our own code that will fill the field
E_KUNNR.
e.g. E_KUNNR = 301.
Activate the include and
Activate the project. Now when ever the SALES ORDER will be created ,
sold-to-party field will come up with a predefined
customer .
FIELD EXITS
The field exits are managed,created,activated through program RSMODPRF. The
field exit is associated with a data element existing in ABAP dictionary and
hence to the screen field using that data element.
The format of field
exit is :
FIELD_EXIT_dataelement_A-Z
or 0-9
If
a particular screen and program name is not specified than the field exit will
effect all the screens containing that data element.
The function
module associated with field exit shows two parameters
INPUT and OUTPUT. Input
parameter contains the data passed to the field exit when the field exit was
invoked by the R/3 , We can write our own code to change the output parameter
depending upon our requirements.
Before the
field exit can have any effect the system profile parameter
ABAP/FIELDEXIT in all the
application servers should be set to YES
ABAP/FIELDEXIT = YES.
Ref
:http://sap.niraj.tripod.com
Submitted By: Thashkil
Islam
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