How to create a droplet with user-data from api v1

Hi community, I need create a new droplet using api v1 and pass the “user data” parameter to create it.

I am trying with:

&user-data=#!/bin/bash echo "hello" >> /var/hello.txt
&user_data=#!/bin/bash echo "hello" >> /var/hello.txt

And url encoded:

&user-data=%23!%2Fbin%2Fbash%0Aecho%20%22hello%22%20%3E%3E%20%2Fvar%2Fhello.txt
&user_data=%23!%2Fbin%2Fbash%0Aecho%20%22hello%22%20%3E%3E%20%2Fvar%2Fhello.txt

But not work. Any help would be appreciated.

Thanks in advance.