Use the format property to specify the integer, currency, accounting, percent, and other formats of the NumberBox value.
The format property can accept the following value types:
Predefined format
See the type property description for a list of accepted values.
Custom format string
Use a LDML pattern to specify a custom format. Refer to the following article for more information: Custom Format String.
Function
A function should apply a custom format to a value and return the formatted value as a string. Functions are useful for advanced formatting.
Object
Full format configuration. The object structure is shown in the format API section.