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- Bash, Concatenating 2 strings to reference a 3rd variable 2 answers
Bash,连接2个字符串以引用第3个变量2个答案
Given:
export A='TEST_'
export B='VAR'
How would I get the value of $TEST_VAR in this case?
在这种情况下,如何获得$ TEST_VAR的值?
Some more conditions:
更多条件:
- should work both on
shandbashof the latest versions.应该适用于最新版本的sh和bash。
- should not use any not pre-installed ubuntu dependencies.
不应该使用任何未预先安装的ubuntu依赖项。
- should be the simplest one liner solution
应该是最简单的单线解决方案
1 个解决方案
#1
You can use indirect variable reference:
您可以使用间接变量引用:
test_var='foo bar baz'
a='test_'
b='var'
c="${a}${b}"
echo "${c}"
test_var
echo "${!c}"
foo bar baz
PS: You should avoid all uppercase variables in Unix to avoid collision with shell internal variables.
PS:你应该避免使用Unix中的所有大写变量来避免与shell内部变量冲突。
#1
You can use indirect variable reference:
您可以使用间接变量引用:
test_var='foo bar baz'
a='test_'
b='var'
c="${a}${b}"
echo "${c}"
test_var
echo "${!c}"
foo bar baz
PS: You should avoid all uppercase variables in Unix to avoid collision with shell internal variables.
PS:你应该避免使用Unix中的所有大写变量来避免与shell内部变量冲突。