Shell programming-annotations, strings and Arrays (iv)

Shell annotations
Use # as the comment symbol
There are no multiple lines of comments in the shell, only one line plus a # number

String manipulation
1. Stitching strings
　　　　

2. Get the string length
String= "KHJF"
echo ${#string}

3. Extracting substrings
String= "Tynam is a good mans"
Echo ${string:1:4}

Array
Equivalent to multiple sets of variables of the same type, without limiting the size of the array in the shell
Defining arrays
In the shell, the array is represented by parentheses, and the array elements are separated by a "space" symbol
General form: array= (value0 value1 value2 value3 value4)
To add an array of values individually: ARRAY[0]=VALUE0
Array[1]=value1

Get array
　　　　

Gets the length of the array
　　　　

Practice

　　　

Answer

　　

Shell programming-annotations, strings and Arrays (iv)