Need to disply 'No Data' in place of blanks

Hello All,

I want to display 'No Data' where ever there are blank spaces in crystal report.

I have tried many formulae but none ofthem worked. Please help me to find the correct one.

if isnull({Query1.Client's Priority}) then 'no data'

else {Query1.Client's Priority}

this doesnt work.

I tried

if({Query1.Client's Priority})=""then 'no data'

else {Query1.Client's Priority}

this doesnt work

Please help asap...Thanks