Shell simple Use (v) variable two

1. Read reading variables from the keyboard

　　

2. Declare/typeset declaring variable types

A. The-i option of the DECLARE command specifies that the variable is an integer type (the default is a string)

　　

B. The-X option of the DECLARE command specifies that the variable is an environment variable (the effect is the same as export)

　　

C. The-R option of the declare command specifies that the variable is a read-only variable

　　

D. +x option for DECLARE command environment variable is a custom variable

　　

3. Array variables

Assignment Method One

　　

Two ways to assign a value

Value Assignment mode three

All elements of an array, subscripts, element lengths, etc.

Cyclic processing

while.sh

#!/bin/Bashvar=([2]=AAA [3]=BBB [4]=CCCCCCCC [1]=... [5]=EFG) forIteminch${var[*]} Do    Echo${item} DoneEcho '************' forIteminch${!var[*]} Do    Echo${item} Done

The results of the operation are as follows:

　　

Shell simple Use (v) variable two