Display Logic and Input

When creating an Application, it is useful to convert between user-friendly strings (usually displaying hbar) and the machine-readable values that contracts and maths depend on (usually in tinybar).

For example, an Account may specify the balance in hbar, but when sending a transaction, it must be specified in tinybar.

The parseUnits will parse a string representing hbar, such as 1.1 into a BigNumber in tinybar, and is useful when a user types in a value, such as sending 1.1 hbar.

The formatUnits will format a BigNumberish into a string, which is useful when displaying a balance.

Units

Decimal Count

A Unit can be specified as a number, which indicates the number of decimal places that should be used.

Examples:

  • 1 hbar in tinybar, has 8 decimal places (i.e. 1 hbar represents 10^8 tinybar)

  • 1 ether in wei, has 18 decimal places (i.e. 1 ether represents 10^18 wei)

  • 1 bitcoin in Satoshi, has 8 decimal places (i.e. 1 bitcoin represents 10^8 satoshi)

Named Units

There are also several common Named Units, in which case their name (as a string) may be used.

NameDecimals

tinybar

0

microbar

2

millibar

5

hbar

8

kilobar

11

megabar

14

gigabar

17

Functions

Formatting

hethers.utils.commify( value ) ⇒ string

Returns a string with value grouped by 3 digits, separated by ,.

commify("-1000.3000");
// '-1,000.3'

Conversion

hethers.utils.formatUnits( value [ , unit = "hbar" ] ) ⇒ string

Returns a string representation of value formatted with unit digits (if it is a number) or to the unit specified (if a string).

hethers.utils.formatUnits(oneGigabar, 'hbar');
// 1000000000.0

hethers.utils.formatUnits(oneHbar, "tinybar");
// '100000000'

hethers.utils.formatUnits(oneGigabar, 17);
// '1.0'

hethers.utils.formatUnits(oneHbar);
// '1.0'

hethers.utils.formatUnits(oneHbar, 8);
// '1.0'

The functions formatEther and parseEther have been replaced with formatHbar and parseHbar.

hethers.utils.formatHbar( value ) ⇒ string

The equivalent to calling formatUnits(value, "hbar").

const value = BigNumber.from("100000000");

formatHbar(value);
// '1.0'

hethers.utils.parseUnits( value [ , unit = "hbar" ] ) ⇒ BigNumber

Returns a BigNumber representation of value, parsed with unit digits (if it is a number) or from the unit specified (if a string).

parseUnits("1.0");
// { BigNumber: "100000000" }

parseUnits("1.0", "gigabar");
// { BigNumber: "1000000000000000000" }

parseUnits("1.0", 17);
// { BigNumber: "100000000000000000" }

parseUnits("121.0", "millibari");
// { BigNumber: "12100000" }

parseUnits("121.0", 5);
// { BigNumber: "12100000" }

hethers.utils.parseHbar( value ) ⇒ BigNumber

The equivalent to calling parseUnits(value, "hbar").

parseHbar("1.0");
// { BigNumber: "100000000" }

parseHbar("-0.5");
// { BigNumber: "--50000000" }

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