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@serenity-is/corelib / formatNumber

Function: formatNumber()

formatNumber(num, format?, decOrLoc?, grp?): string

Defined in: src/base/formatting.ts:337

Formats a number using .NET-style numeric format strings and locale settings.

Parameters

num

number

Value to format; null / undefined yields "" and NaN yields nanSymbol.

format?

string

Format specifier. "g" (general), "d"/"x"/"e"/"f"/"n"/"c"/"p", or a custom pattern ("#,##0.00", "000", etc.).

decOrLoc?

Either a Locale / NumberFormat object, or the decimal separator string for a lightweight inline locale.

string | NumberFormat

grp?

string

Group separator when decOrLoc is a decimal-separator string. Ignored otherwise.

Returns

string

The formatted number string, applying grouping, decimal separator, and locale symbols from decOrLoc or Culture.

Default Value

"g".

Remarks

  • "n" / "N" insert grouping; "c"/"p" append currencySymbol/percentSymbol (percent multiplies by 100).
  • Custom patterns quote literals with ' and escape with ``.

Example

formatNumber(1234.5, "n2"); // e.g. "1,234.50" depending on Culture
formatNumber(0.42, "p0");   // e.g. "42%"