PHP 5/MySQL Programming- P31 docx

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//check for two pairs
if ($numPairs = = 2){
print “You have two pairs!<br>\n”;
$payoff = 1;
} // end if
Of course, you’re welcome to change the payoffs. As it stands, this game is incred-
ibly generous, but that makes it fun for the user.
Looking for Three of a Kind and a Full House
I combine the checks for three of a kind and full house (which is three of a kind
and a pair). The code first checks for three of a kind by looking at
$numThrees. If
the user has three of a kind, it then checks for a pair. If both these conditions are
true, it’s a full house and the user is rewarded appropriately. If there isn’t a pair,
the user gets a meager reward for the three of a kind.
//check for three of a kind and full house
if ($numThrees = = 1){
if ($numPairs = = 1){
//three of a kind and a pair is a full house

print “You have a full house!<br>\n”;
$payoff = 5;
} else {
print “You have three of a kind!<br>\n”;
$payoff = 2;
} // end ‘pair’ if
} // end ‘three’ if
Checking for Four of a Kind and Five of a Kind
Checking for four- and five of a kind is trivial. Looking at the appropriate vari-
ables is the only necessity.
//check for four of a kind
if ($numFours = = 1){
print “You have four of a kind!<br>\n”;
$payoff = 5;
} // end if
//check for five of a kind
if ($numFives = = 1){
print “You got five of a kind!<br>\n”;
$payoff = 10;
} // end if
Checking for Straights
Straights are a little trickier, because two are possible. The player could have the
values
1-5 or 2-6. To check these situations, I used two compound conditions. A
compound condition is made of a number of ordinary conditions combined with
special logical operators. Look at the straight-checking code to see an example:
//check for straights
if (($numVals[1] = = 1)
&& ($numVals[2] = = 1)
&& ($numVals[3] = = 1)

&& ($numVals[4] = = 1)
&& ($numVals[5] = = 1)){
print “You have a straight!<br>\n”;
$payoff = 10;
} // end if
if (($numVals[2] = = 1)
&& ($numVals[3] = = 1)
&& ($numVals[4] = = 1)
&& ($numVals[5] = = 1)
&& ($numVals[6] = = 1)){
print “You have a straight!<br>\n”;
$payoff = 10;
Notice how each if statement has a condition made of several subconditions
joined by the
&& operator? The && operator is called a
Boolean and
operator. You
can read it as
and.
The condition is evaluated to TRUE only if all the subconditions
are true.
The two conditions are similar to each other, simply checking the two possible
straight situations.
Printing the Results
The program’s last function prints variable information to the user. The $cash
value describes the user’s current wealth. Two hidden elements store informa-
tion the program needs on the next run. The
secondRoll element contains a TRUE
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or FALSE value indicating whether the
next
run should be considered the second
roll. The
cash element describes how much cash should be attributed to the
player on the next turn.
function printStuff(){
global $cash, $secondRoll;
print “Cash: $cash\n”;
//store variables in hidden fields
print <<<HERE

<input type = “hidden”
name = “secondRoll”
value = “$secondRoll”>
<input type = “hidden”
name = “cash”
value = “$cash”>
HERE;
} // end printStuff
?>
</form>
</html>
Summary
You are rounding out your basic training as a programmer, adding rudimentary
looping behavior to your bag of tricks. Your programs can repeat based on con-
ditions you establish. You know how to build
for loops that work forwards, back-
wards, and by skipping values. You also know how to create
while loops. You
know the guidelines for creating a well-behaved loop and how to form arrays
manually and with the
array() directive. Stepping through all elements of an
array using a loop is possible, and your program can keep track of persistent vari-
ables by storing them in form fields in your output pages. You put all these skills
together to build an interesting game. In chapter 5 you extend your ability to
work with arrays and loops by building more-powerful arrays and using special-
ized looping structures.
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CHALLENGES
1. Modify the Poker Dice game in some way. Add a custom background,
change the die images, or modify the payoffs to balance the game to your
liking.
2. Write the classic I’m Thinking of a Number game. Have the computer ran-
domly generate a number and let the user guess its value. Tell the user if he
is too high, too low, or correct. When he guesses correctly, tell how many
turns it took. No arrays are necessary for this game, but you must store
values in hidden form elements.
3. Write I’m Thinking of a Number in reverse. This time the user generates
a random number between 1 and 100 and the computer guesses the number.
Let the user choose from too high, too low, or correct. Your algorithm
should always be able to guess the number in seven turns or fewer.
4. Write a program that deals a random poker hand. Use playing card images
from or another source. Your program
does not need to score the hand. It simply needs to deal out a hand of five
random cards. Use an array to handle the deck.
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