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Description
Initiates in the following situations:
-
When your form design and data merge into your finished form.
-
When a change occurs to any value that the calculation is
dependent on, such as the value of a particular field, unless the
form filler has manually overridden the calculated value. As a result,
the object will display the return value of the event. The properties
for manually overridden fields are located in the Value tab of the
Object palette.
-
When a field loses focus; for example, when a form filler
clicks or uses the Tab key to exit a field.
When using the
calculate
event
to perform calculations or scripts, consider the following potential
issues:
-
Calculations and scripts on the
calculate
event
must not make any changes to the structure of the form, except for
the form field and data values.
-
Content inserted by the
calculate
event
must conform to the associated validations for the object; otherwise,
validation errors will occur.
-
Calculations and scripts must not include an infinite loop
because it causes the form to update the value continuously. For
example, a script that increments the value of a field as part of
a looping expression, such as a
while
or
for
loop,
could create an infinite loop.
-
The last expression evaluated in the
calculate
event
is used to populate the value of the current form object. For example,
if the script on the
calculate
event first sets
the value of the current field to 500 and then sets the value of
another field to 1000, both fields will display the value 1000 at
run time. As a result, you need to limit the scripting that you
add to the
calculate
event to those that deal specifically
with setting the value of the current field.
Support
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Client application
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Availability
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Acrobat and Adobe Reader
|
yes
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HTML browser
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yes
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Example
Use
the
calculate
event for updating numeric values
in fields because this event initiates immediately after most other
events. For example, on a purchase order form, you can use the
calculate
event
for a field to determine the percentage of sales tax due based on
the cost of the order. The calculation will initiate every time
a change is made to the values in the form fields, ensuring that the
value displayed for the sales tax is always correct.
However,
because the
calculate
event can initiate many times,
you must ensure that the calculation or script you add to the event
will not cause data values to increment unnecessarily. For example,
if your sales tax calculation adds the value of the sales tax to
the total cost each time the
calculate
event initiates,
the resulting total cost value on your form may be too large.
For
a detailed example of using the
calculate
event,
see
Calculating the field sums
.
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