This task requires the System Administrator or System Customizer security role A defined set of privileges. The security role assigned to a user determines which tasks the user can perform and which parts of the user interface the user can view. All users must be assigned at least one security role in order to access the system. or equivalent permissions. Customization tasks can be performed only while you are online. More information: Customization Permissions
You should always test your scripts before publishing your customizations.
In the Navigation Pane, click Settings, click Customization, and then click Customize Entities.
Open the entity that contains the form with the script you want to test, and then click Forms and Views.
Click Form, then on the Actions toolbar, click More Actions, and then click Edit.
On the Preview menu, click Create Form, Update Form, or Read-Only Form.
If you have added an OnLoad event for the form, when you open the form in each mode, verify that your event executed as expected.
If your code depends on data existing in the form when it loads, you may want to test your script in an onChange or onSave event so that you can enter sample data into the form. The Update Form will open with no data.
If you have added an onChange event for a field, for create and update modes, enter the data in the field and verify that the event executes as expected.
If you have added an onSave event for the form, for create and update modes, on the Form toolbar, click Simulate Form Save to see if the event executes as expected.
To close the Preview form, on the File menu, click Close.