attachMetadataJson

readonly attachMetadataJson!: 
    label: numebr | bigint,
    metadataJson: any
) => TxBuilderRunner

• label: number | bigint;
• metadataJson: any;

like attachMetadata, adds a metadata entry for the given label, or overrides if the same label was already present.

metadataJson is a jsavascript value converted as follows

• object -> TxMetadatumMap
• array -> TxMetadatumList
• string -> TxMetadatumText (use attachMetadataJsonWithConversion for explicit conversion to TxMetadatumBytes, or consider using attachMetadata)
• number -> TxMetadatumInt
• bigint -> TxMetadatumInt

returns a reference to the same TxBuilderRunner.