Bash: Use Associative Array
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Simple example
cat bash-associative-array-simple.sh
#!/bin/bash
declare -A content_cats
content_cats=(
["WordPress"]="This category contains..."
["MediaWiki"]="This category contains..."
["HTML and CSS"]="This category contains..."
["Linux Desktop"]="This category contains..."
["Linux Server"]="This category contains..."
)
for key in "${!content_cats[@]}"; do
echo -e "$key \t => ${content_cats[$key]}"
done
./bash-associative-array-simple.sh
MediaWiki => This category contains...
Linux Desktop => This category contains...
HTML and CSS => This category contains...
Linux Server => This category contains...
WordPress => This category contains...
Extended example
As you can see in the above example the array content is printed in wrong order. We can solve this issue by the following approach, provided by Jonathan Leffler at Stack Overflow, where is used one additional array that holds the proper order.
cat bash-associative-array-extended.sh
#!/bin/bash
declare -A content_cats
content_cats=(
["WordPress"]="This category contains..."
["MediaWiki"]="This category contains..."
["HTML and CSS"]="This category contains..."
["Linux Desktop"]="This category contains..."
["Linux Server"]="This category contains..."
)
declare -a content_cats_order
content_cats_order=(
"WordPress"
"MediaWiki"
"HTML and CSS"
"Linux Desktop"
"Linux Server"
)
for key in "${content_cats_order[@]}"
do
echo -e "$key \t => ${content_cats[$key]}"
done
./bash-associative-array-extended.sh
WordPress => This category contains...
MediaWiki => This category contains...
HTML and CSS => This category contains...
Linux Desktop => This category contains...
Linux Server => This category contains...
Reference manual
References
- Stack Overflow: How to keep associative array order?
- Stack Overflow: What does declare ‑A do in Linux shell?
- Viet Nguyen Tien: How to use arrays in Bash
