Different ways to find length of the String in UNIX?

Length of the string is the number of characters in the strings content. There are many different ways to compute the length of the string. Here we will see some of the ways to find the length of the string using the shell script. 

> cat length.sh
#!/bin/bash

str="Unix"

#1. using the wc command

len=`echo $str|wc -c`
echo "length of $str=$len"

#2. using the awk command

len=`echo $str|awk '{print length}'`

#3. using the expr command

len=`expr length "$str"`
echo "length of $str=$len"

#4. using the shell built in hash(#)

echo "length of $str=${#str}"