Use of serial number self-increment key

Since the output sequence number is required in the template, it is not guaranteed to be sequential if it is extracted from the database.

In the template I use the Foreach Loop, and the manual sees the use of foreach

But I still did not learn the use of key from the manual. Try to use

As a result, but starting from 0.

I want to start from 1. Then the first thing I think about is whether the key can set the initial value, and no usage is found. Had to check the Internet. The result of a solution that I see is {$key +1}, that's great.

At the same time I looked up the manual to see Volist in this area has a powerful function, but has not been used.

Use of serial number self-increment key