Interface Promise<R>

then

• then<U>(onFulfilled?: function, onRejected?: function): Promise<U>

• onFulfilled is called when/if "promise" resolves. onRejected is called when/if "promise" rejects. Both are optional, if either/both are omitted the next onFulfilled/onRejected in the chain is called. Both callbacks have a single parameter , the fulfillment value or rejection reason. "then" returns a new promise equivalent to the value you return from onFulfilled/onRejected after being passed through Promise.resolve. If an error is thrown in the callback, the returned promise rejects with that error.

  Type parameters

  • U

  Parameters

  • Optional onFulfilled: function

    called when/if "promise" resolves

    • • (value: R): U | Thenable<U>

      • Parameters

        • value: R

        Returns U | Thenable<U>

  • Optional onRejected: function

    called when/if "promise" rejects

    • • (error: any): U | Thenable<U>

      • Parameters

        • error: any

        Returns U | Thenable<U>

  Returns Promise<U>