Interview › Scripting (Bash, Groovy)
How do you get the length of a string or the number of elements in an array? [Intermediate]
Answer
${#var} returns the length of a string, and ${#array[@]} returns the number of elements in an array. These are Bash built-ins and do not require external commands.
Technical explanation
For strings, the count is character count in the shell's current handling, not necessarily display width.
For arrays, ${#array[@]} counts elements, while ${#array[index]} gets the length of one element.
Use array length checks before indexing when empty arrays are possible.
Hands-on example
name="orders-api"echo "string length=${#name}"
services=(api worker scheduler)
echo "service count=${#services[@]}"
echo "first name length=${#services[0]}"Preparing for an interview?
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