Concat strings in a shell script [duplicate]

问题

This question already has answers here:

How to concatenate string variables in Bash (30 answers)

Closed 3 years ago.

How can I concat strings in shell? Is it just...

var = 'my';
var .= 'string';

?

回答1:

How about this:

var="${var}string"

回答2:

It depends on the shell, but since question was tagged bash:

var='my'
var=$var'string'

回答3:

No. For various reasons.

# most sh-compatible shells
var="my"
var="$var string"

# advanced shells
var="my"
var+=" string"

来源：https://stackoverflow.com/questions/9445259/concat-strings-in-a-shell-script