I will not give you the source code (Cause I am a witch) but if you look up If statements and how to get info out of a db then you will be all set. You will use something like
if ($givenusername == $realusername){
if ($givenpassword == $givenpassword){
echo "Way to go you have the right username and password!";
}else{
echo "Not a good password";
}else {
echo "Not a good username";
}
Something like that. I just bounced that off my memory. But that has failed me many times. You should get the idea though. You will also use the != which means not equal to or does not match. Lata!
Ziggs