Friday, June 3, 2016

X++ tips and tricks: Passing parameters in Microsoft Dynamics AX

Args is your companion in the world of X++ tips and tricks. Args is an abbreviation for arguments. It allows you to pass information from one object to another newly created object. I utilize it frequently to pass the objects, records, strings, etc that I need to have in scope while accessing the object from another object. It’s very easy to utilize the Args class to get the desired result you’re looking for.
The following example demonstrates how to create an instance of the Args class:

Declaration of Args

Args  args = new Args();
CustTable  custTable;

Setting record is Args

select custTable where custTable.AccountNum == ‘XXXX’
if(custTable)
{
args.record(custTable);
}

Some important methods of Args class

Caller

Get or sets the instance of the object that created this instance of the Args class.

Name

Gets and sets the name of the application object to call.

Parm

Gets or sets a string that specifies miscellaneous information for the called object.

parmEnum

Gets or sets the enumeration value of the enumeration type that is specified in the parmEnumType method.

parmEnmType

Gets or sets the ID value of any enumeration type.

ParmObject

Gets or sets an instance of any object to pass, to the called object.

Record

Gets and sets the record from the table on which the caller object is working.

Sample Code  For Setting Value in Args

Create an instance of the Args and custom class.
 Args  args;
CustTable  custTable;
//custom class object to pass
Student student= new Student();
args = new args();
Set the parameter which you want to pass. If you just want to pass a simple string you can do it like this
 args.parm("Hello World");
If you want to pass an enum value you can do so via following code.
args.parmEnum( NoYesEnumValue.selection() );
args.parmEnumType( EnumNum( NoYes ) );
If you want to pass table buffer  in parameter
args.record( EmplTable );
If we want pass a more complex set of parameters, you can develop your own class just for passing those parameters.
student.parmName(‘William’ );
student.parmRollNum(‘st-123‘);
args.parmObject(student);
If you to pass records from a table, use following code.
select custTable where custTable.AccountNum == ‘XXXX’
if(custTable)
{
args.record(custTable);
}

Sample Code  For Getting  Value From Args

Create an instance of the Args class and your custom class.
Args   args;
CustTable  custTable;
//custom class object to pass
Student student= new Student();
args = new args();
Check that the passed arguments are not null
if( element.args() )
{
.....
}
Get string value
strValue.text( element.args().parm() );
Check parmEnum is not null and then get enum parameter
if( element.args().parmEnumType() == EnumNum( NoYes ) )
{
NoYesEnumValue.selection( element.args().parmEnum() );
}
Check parmEnum is not null and then get object
if( element.args().parmObject() )
{
student = element.args().parmObject();
}
Check that the table buffer is not null and then get record.
if( element.args().record() && element.args().record().TableId == TableNum( CustTable ) )
{
custTable=  element.args().record();
}