Replace specific columns

Shell Programming and Scripting
1

hi All,

Thi sis very urgent.

I have large files with pipe delimited.
For example:
1.txt
1001024|120|9|-0.0|#|
1001025|120|9|#|
1001026|120|9|#|
1001032|120|2|-0.0|#|
1002026|110|9|#|
1002027|110|9|-0.0|#|
1002028|120|1|1.0|#|

I need to replace the 4th filed if it is # by |-|
my final txt file should like like below;

2.txt (out put)
1001024|120|9|-0.0|#|
1001025|120|9|-|
1001026|120|9|-|
1001032|120|2|-0.0|#|
1002026|110|9|-|
1002027|110|9|-0.0|#|
1002028|120|1|1.0|#|

Please help
Thanks in advance
JS

2 
awk '{FS=OFS="|"}$4=="#"{$4="-"}1'
3

A heaven thanks ...