Use isSubnameAvailable to check if a subname can be registered. 
const response = client.isSubnameAvailable("ns.myensname.eth");
const isAvailable = response.isAvailable; // true if the subname is available, false if already taken.

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Parameters

  • subname: Subname to check availability for (e.g., "ns.myensname.eth")

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Return Type

  • isAvailable: true if the subname is available, false if already taken.
Always check subname availability before attempting to create or update a subname.
It may overwrite the existing subname.