How to include file in a bash shell script

Question

Is there a way to include another shell script in a shell script to be able to access its functions?

Like how in PHP you can use the include directive with

Answer 1

Above answers are correct, but if run script in other folder, there will be some problem.

For example, the a.sh and b.sh are in same folder, a include b with . ./b.sh to include.

When run script out of the folder, for example with xx/xx/xx/a.sh, file b.sh will not found: ./b.sh: No such file or directory.

I use

. $(dirname "$0")/b.sh