ref

A builder function that sets the reference block for a transaction.

The reference block specifies an expiration window (measured in blocks) during which a transaction is considered valid by the network. A transaction will be rejected if it is submitted past its expiry block. Flow calculates transaction expiry using the reference block field.

Import

You can import the entire package and access the function:

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import * as sdk from "@onflow/sdk"

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sdk.ref(refBlock)

Or import directly the specific function:

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import { ref } from "@onflow/sdk"

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ref(refBlock)

Usage

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import * as fcl from "@onflow/fcl";

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// Set specific reference block for transaction

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await fcl.send([

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fcl.transaction`

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transaction {

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prepare(account: AuthAccount) {

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log("Transaction with custom reference block")

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}

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}

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`,

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fcl.ref("a1b2c3d4e5f6789..."), // Custom reference block ID

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fcl.proposer(fcl.authz),

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fcl.payer(fcl.authz),

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fcl.authorizations([fcl.authz]),

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fcl.limit(100)

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]);

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// Usually, you don't need to set reference block manually

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// as FCL will automatically set it to the latest block

Parameters

refBlock

• Type: string
• Description: The reference block ID

Returns

InteractionBuilderFn

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export type InteractionBuilderFn = (

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ix: Interaction

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) => Interaction | Promise<Interaction>

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