Linux shell Script programming Case Condition statement

1, determine whether a number is in the one-way.

#!/bin/Bashread-P"pls input a number:"N Case "$n" inch    1)        Echo "variable is 1"        ;; 2)        Echo "variable is 2"        ;; 3)        Echo "variable is 3"        ;; *)        Echo "pls input a number between 1 and 3"exit;Esac

2, multi-level if statement rewriting

#!/bin/Bashread-P"pls input a number:"Nif[$n-eq1]; Then    Echo "$n is a variable 1"elif[$n-eq2]; Then    Echo "$n is a variable 2"elif[$n-eq3]; Then    Echo "$n is a variable 3"Else    Echo "pls input a number between 1 and 3"fi

3,if. else nesting, implementing

#!/bin/Bashread-P"pls input a number:"Nif[$n-eq1]; Then    Echo 1Else    if[$n-eq2]; Then        Echo 2    elif[$n-eq3]; Then        Echo 3    Else        Echo "pls input a number [1-3]"    fifi

4, judging the score level

#!/bin/Bashread-P"pls input score to test level:"scoreif[$score-ge -]; Then    Echo "Excellent"elif[$score-ge the]; Then    Echo "Good"elif[$score-ge -]; Then    Echo "Medium"elif[$score-ge -]; Then    Echo "Pass"Else    Echo "inferior lattice"fi

5, add color to text

#!/bin/Bashred_color='\e[1;31m'Green_color='\e[1;32m'Yellow_color='\e[1;33m'Blue_color='\e[1;34m'Reset_color='\e[0m'Echo '    1, Goku2, eight commandments3, Tang's monk4, White Dragon Horse'Read-p"pls input a number:"N Case$ninch    1)        Echo-E"${red_color} Goku ${reset_color}"        ;; 2)        Echo-E"${green_color} Eight commandments ${reset_color}"        ;; 3)        Echo-E"${yellow_color} tang priest ${reset_color}"        ;; 4)        Echo-E"${blue_color} white Dragon horse ${reset_color}"        ;; *)        Echo "You need input a number in {1|2|3|4}"Esac

Another way to do this:

#!/bin/Bashred_color='\e[1;31m'Green_color='\e[1;32m'Yellow_color='\e[1;33m'Blue_color='\e[1;34m'Reset_color='\e[0m'functionmenu () {Cat<<END1, Goku2, eight commandments3, Tang's monk4, White Dragon Horse End}functionSelect_type () {Read-P"pls input a number:"N Case$ninch            1)                Echo-E"${red_color} Goku ${reset_color}"                ;; 2)                Echo-E"${green_color} Eight commandments ${reset_color}"                ;; 3)                Echo-E"${yellow_color} tang priest ${reset_color}"                ;; 4)                Echo-E"${blue_color} white Dragon horse ${reset_color}"                ;; *)                Echo "You need input a number in {1|2|3|4}"        Esac}functionMain () {menu Select_type}main

Read command line arguments, set color for content

#!/bin/Bashred_color='\e[1;31m'Green_color='\e[1;32m'Yellow_color='\e[1;33m'Blue_color='\e[1;34m'Reset_color='\e[0m'if[$#-ne2]; Then    Echo "Usage $ input {red|green|yellow|blue}"Exitfi Case$2 inchred)Echo-E"${red_color}$1${reset_color}"        ;; Green)Echo-E"${green_color}$1${reset_color}"        ;; Yellow)Echo-E"${yellow_color}$1${reset_color}"        ;; Blue)Echo-E"${blue_color}$1${reset_color}"        ;; *)            Echo "usage $ input {red|green|yellow|blue}"ExitEsac

Modify into function call mode

#!/bin/BashfunctionTocolor () {Red_color='\e[1;31m'Green_color='\e[1;32m'Yellow_color='\e[1;33m'Blue_color='\e[1;34m'Reset_color='\e[0m'        if[$#-ne2]; Then            Echo "Usage $ input {red|green|yellow|blue}"Exitfi         Case$2 inchred)Echo-E"${red_color}$1${reset_color}"                ;; Green)Echo-E"${green_color}$1${reset_color}"                ;; Yellow)Echo-E"${yellow_color}$1${reset_color}"                ;; Blue)Echo-E"${blue_color}$1${reset_color}"                ;; *)                    Echo "usage $ input {red|green|yellow|blue}"ExitEsac}functionMain () {Tocolor $1$2}main $*

Linux shell Script programming Case Condition statement