Check return code in bash while capturing text - bash

Question

When running an ldapsearch we get a return code indicating success or failure. This way we can use an if statement to check success.
On failure when using debug it prints if the cert validation failed. How can I capture the output of the command while checking the sucess or failure of ldapsearch?
ldapIP=`nslookup corpadssl.glb.intel.com | awk '/^Address: / { print $2 }' | cut -d' ' -f2`
server=`nslookup $ldapIP | awk -F"= " '/name/{print $2}'`
ldap='ldapsearch -x -d8 -H "ldaps://$ldapIP" -b "dc=corp,dc=xxxxx,dc=com" -D "name#am.corp.com" -w "366676" (mailNickname=sdent)"'
while true; do
if [[ $ldap ]] <-- capture text output here ??
then
:
else
echo $server $ldapIP `date` >> fail.txt
fi
sleep 5
done

Answer 1

As #codeforester suggested, you can use $? to check the return code of the last command.
ldapIP=`nslookup corpadssl.glb.intel.com | awk '/^Address: / { print $2 }' | cut -d' ' -f2`
server=`nslookup $ldapIP | awk -F"= " '/name/{print $2}'`
while true; do
captured=$(ldapsearch -x -d8 -H "ldaps://$ldapIP" -b "dc=corp,dc=xxxxx,dc=com" -D "name#am.corp.com" -w "366676" "(mailNickname=sdent)")
if [ $? -eq 0 ]
then
echo "${captured}"
else
echo "$server $ldapIP `date`" >> fail.txt
fi
sleep 5
done
EDIT: at #rici suggestion (and because I forgot to do it)... ldap needs to be run before the if.
EDIT2: at #Charles Duffy suggestion (we will get there), we don't need to store the command in a variable.