#!/bin/bash
# 
#  Decription: 
#		A Shell script used to download the imges from Internet.
#  Author:
#       Long Luo
#  Date:
#       2014-09-11 00:16:59
#

BASE_URL="https://s.yimg.com/zz/combo?a/i/us/nws/weather/gr/"

# declare STIRNG variable
STRING="Beginning Image download..."

#print var on screen 
echo $STRING

sleep 1
echo "...."

BIG_PNG="ds.png"
PNG=".png"

echo "url="${BASE_URL}
echo "big png="${BIG_PNG}

for ((i=0; i<49;i++)); do
	echo IMG_URL=${BASE_URL}${i}${BIG_PNG}
	echo "final url="${IMG_URL}

	curl ${BASE_URL}${i}${BIG_PNG} -o small/${i}${PNG}
	sleep 1

done

方法2:

# Method 2

URL_ARRAY=(
'https://s.yimg.com/zz/combo?a/i/us/nws/weather/gr/0d.png'
'https://s.yimg.com/zz/combo?a/i/us/nws/weather/gr/1d.png'
)

NAME_ARRAY=(
'file1.jpg'
'file2.jpg'
)

ELEMENTS=${#URL_ARRAY[@]}

for (( i=0;i<ELEMENTS;i++)); do
	echo ${URL_ARRAY[${i}]}
	echo "saved as ${NAME_ARRAY[${i}]}"
 	curl ${URL_ARRAY[${i}]} -o images/${NAME_ARRAY[${i}]}
	sleep 1
	
done