Loop through an array of strings in Bash?

Question

I want to write a script that loops through 15 strings (array possibly?) Is that possible?

Something like:

for databaseName in listOfNames
then
  # D         


        

Answer 1

In the same spirit as 4ndrew's answer:

listOfNames="RA
RB
R C
RD"

# To allow for other whitespace in the string:
# 1. add double quotes around the list variable, or
# 2. see the IFS note (under 'Side Notes')

for databaseName in "$listOfNames"   #  <-- Note: Added "" quotes.
do
  echo "$databaseName"  # (i.e. do action / processing of $databaseName here...)
done

# Outputs
# RA
# RB
# R C
# RD

B. No whitespace in the names:

listOfNames="RA
RB
R C
RD"

for databaseName in $listOfNames  # Note: No quotes
do
  echo "$databaseName"  # (i.e. do action / processing of $databaseName here...)
done

# Outputs
# RA
# RB
# R
# C
# RD

Notes

1. In the second example, using listOfNames="RA RB R C RD" has the same output.

Other ways to bring in data include:

• stdin (listed below),
• variables,
• an array (the accepted answer),
• a file...

Read from stdin

# line delimited (each databaseName is stored on a line)
while read databaseName
do
  echo "$databaseName"  # i.e. do action / processing of $databaseName here...
done # <<< or_another_input_method_here

2. the bash IFS "field separator to line" [1] delimiter can be specified in the script to allow other whitespace (i.e. IFS='\n', or for MacOS IFS='\r')
3. I like the accepted answer also :) -- I've include these snippets as other helpful ways that also answer the question.
4. Including #!/bin/bash at the top of the script file indicates the execution environment.
5. It took me months to figure out how to code this simply :)

Other Sources (while read loop)