#!/bin/bash RED_COLOR="E[1;31m" GREEN_COLOR="E[1;32m" YELLOW_COLOR="E[1;33m" BLUE_COLOR="E[1;34m" RES="E[0m" function usage(){ echo "USAGE: $0 {1|2|3|4}" exit 1 } function menu(){ cat << END ============================= 1.apple 2.pear 3.banana 4.cherry ============================= END } function choice(){ read -p "Please input a number to choice." num case $num in 1) echo -e "${RED_COLOR}apple${RES}" ;; 2) echo -e "${GREEN_COLOR}pear${RES}" ;; 3) echo -e "${YELLOW_COLOR}banana${RES}" ;; 4) echo -e "${BLUE_COLOR}cherry${RES}" ;; *) usage esac } function main(){ menu choice } main