Assign to dynamic variable name in Bash [duplicate

问题:

This question already has answers here:

Dynamic variable names in Bash (13 answers)

how to use variable variable names in bash script [duplicate] (1 answer)

Closed 3 years ago.

How do I assign a value to variable that has a variable in its name?

var1="file"
var2_$var1="folder"

The code above gives me the error -bash: var2_file=folder: command not found. I was curious to know how to assign to a variable with another variable in its name.

Version of Bash is "GNU bash, version 4.1.2"

回答1:

With bash you can use declare:

declare var2_$var1="123"

回答2:

How about using another variable to hold the dynamic name and use it for retrieving the value after setting?

new_var=var2_$var1
declare var2_$var1="123"
echo "${!new_var}" # => 123

Unfortunately, Bash doesn't allow declare $new_var="123" - that would have made this a little prettier.