bash loop through all chars in string [duplicate]

Question

How should I loop through all chars in a string.

My pseudocode

stringVar="abcde"

for var in stringvar
{
   do some things with var
}

result i need
a

b

c

d

I want to loop all the vars but i can only get it to work with a whitespace splitted var like

 stringVar="a b c"


for var in stringVar; do
   echo $var
done;

result

a

b

c

but i cant do it for a string that isnt split with whitespaces.

The question is flagged as duplicate but not one of the answers (with upvotes) is available in the linked questions..

Answer 1

You can use read for that:

string="abcde"
while read -n 1 char ; do
    echo "$char"
done <<< "$string"

Using -n 1 read will read one character at a time. However, the input redirection <<< adds a newline to the end of $string.

Answer 2

stringVar="abcde"
for ((i=1;i<=${#stringVar};i++)); do
  echo ${stringVar:$i-1:1}
done

Output:

a
b
c
d
e