All Databases Inside Mac - AppleEvents

Adding Parameters to an Apple Event

You can use the AEPutParamPtr or AEPutParamDesc function to add

parameters to an Apple event. When you use either of these functions, the

Apple Event Manager adds the specified parameter to the Apple event.

Use the AEPutParamPtr function when you want to add data specified in a

buffer as the parameter of an Apple event. You specify the Apple event, the

keyword of the parameter to add, the descriptor type, a buffer that contains the

data, and the size of this buffer as parameters to the AEPutParamPtr

function. The AEPutParamPtr function creates the descriptor record and

adds the parameter to the Apple event.

For example, this code adds a parameter to the Multiply event using the

AEPutParamPtr function.

# define keyOperand1 'OPN1'

long number1;

AppleEvent theAppleEvent;

OSErr myErr;

number1 = 10;

myErr = AEPutParamPtr(& theAppleEvent, keyOperand1,

typeLongInteger,& number1, sizeof( number1));

In this example, the Apple Event Manager adds the parameter containing

the first number to the specified Apple event.

Use the AEPutParamDesc function to add data specified in a

descriptor record to an Apple event. The descriptor record you specify must

have been previously created using the AECreateDesc or AEDuplicateDesc

function.

You specify the descriptor type, a buffer that contains the data, and the size of

this buffer as parameters to the AECreateDesc function. The AECreateDesc

function returns the descriptor record that describes the data.

This example creates a descriptor record for the second parameter of the

Multiply event:

long number2;

AEDesc multParam2Desc

OSErr myErr;

number2 = 8;

myErr = AECreateDesc( typeLongInteger, & number2, sizeof( number2),

&multParam2Desc);

In this example, the AECreateDesc function creates a descriptor record

with the typeLongInteger descriptor type and the data identified in the number2

variable.

Once you have created a descriptor record, you can use AEPutParamDesc to

add the data to a parameter of an Apple event. You specify the Apple event to add

the parameter to, the keyword of the parameter, and the

descriptor record of the parameter as parameters to the AEPutParamDesc

function.

This example adds a second parameter to the Multiply event using the

AEPutParamDesc function.

#define keyOperand2 'OPN2'

myErr = AEPutParamDesc(& theAppleEvent,

keyOperand2,&multParam2Desc);

This example adds the keyOperand2 keyword and the descriptor record

created in the previous example as the second parameter to the specified Apple

event.

The previous examples showed how to add parameters to the imaginary

Multiply event. After adding parameters to an Apple event, you can send the

Apple event using the AESend function.

Referenced by (10):