69 lines
2.1 KiB
Plaintext
69 lines
2.1 KiB
Plaintext
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_title: Display Logic and Input
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_section: Display Logic and Input
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When creating an Application, it is useful to convert between
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user-friendly strings (usually displaying **ether**) and the
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machine-readable values that contracts and maths depend on
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(usually in **wei**).
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For example, a Wallet may specify the balance in ether, and
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gas prices in gwei for the User Interface, but when sending
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a transaction, both must be specified in wei.
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The [parseUnits](unit-conversion) will parse a string representing
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ether, such as ``1.1`` into a [BigNumber](bignumber) in wei, and is
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useful when a user types in a value, such as sending 1.1 ether.
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The [formatUnits](unit-conversion) will format a [BigNumberish](bignumberish)
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into a string, which is useful when displaying a balance.
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_subsection: Units
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_heading: Decimal Count
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The //unit// specified may be an integer, which indicates how
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many decimal place the unit has. For example, 1 ether has 18 decimal
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places for wei, and if this library were used with Bitcoin, 1 BTC
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has 8 decimal places for satoshis.
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_heading: Named Units
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In addition to specifying //unit// as a number of decimals, there
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are several common units, which can be passed in as a string:
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- **wei** --- 0
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- **kwei** --- 3
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- **mwei** --- 6
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- **gwei** --- 9
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- **szabo** --- 12
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- **finney** --- 15
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- **ether** --- 18
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_subsection: Functions
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_heading: Formatting
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_property: utils.commify(value) => string
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Returns a string with value grouped by 3 digits, separated by ``,``.
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_heading: Conversion @<unit-conversion>
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_property: utils.formatUnits(value [ , unit = "ether" ] ) => string
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Returns a string representation of //value// formatted with //unit//
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digits (if it is a number) or to the unit specified (if a string).
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_property: utils.formatEther(value) => string
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The equivalent to calling ``formatUnits(value, "ether")``.
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_property: utils.parseUnits(value [ , unit = "ether" ] ) => [BigNumber](bignumber)
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Returns a [BigNumber](bignumber) representation of //value//, parsed with
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//unit// digits (if it is a number) or from the unit specified (if
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a string).
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_property: utils.parseEther(value) => [BigNumber](bignumber)
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The equivalent to calling ``parseUnits(value, "ether")``.
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