Shell split string stored in array

In shell programming, it is often necessary to divide a string separated by a particular delimiter into an array, and in most cases we first think of using awk
However, it is more convenient to actually use the shell's own split array function. If
A= "One,two,three,four"

To split $ A apart, you can:
Old_ifs= "$IFS"
Ifs= ","
Arr= ($a)
ifs= "$OLD _ifs"
For S in ${arr[@]}
Do
echo "$s"
Done

The above code will output
One
Both
Three
Four

Arr= ($a) to split the string $ A into an array $arr ${arr[0]} ${arr[1]} ... Store the segmented array, respectively, 1th 2 ... Item, ${arr[@]} stores the entire array. The variable $ifs stores the delimiter, and here we set it to a comma "," old_ifs is used to back up the default delimiter, which is restored by default when it is finished.

to put a string cut in a file into an array

7481|1|1359475743|1014|1|14.223.145.61:1609
7482|1|1359475752|1014|3|14.223.145.61:1609
7483|1|1359475754|3544|1|121.61.222.187:2971
7484|1|1359475758|11541|3|183.187.51.156:2582

Filename= ' aa.log '   #文件路径
old_ifs= "$IFS"
ifs= "|"
I=0
If [-f ${filename}];then
   while read line
   do
     arr= ( $line)
     echo ${arr[0]}_${arr[1]}_${arr[2]}_${arr[3]}_${arr[4]}_${arr[5]}_${i}
     i=$ ((i+1))
   done < ${filename}
Fi