使用 if 语句在 while 循环中回显文本

Question

I'm working on an assignment right now. The loop is supposed to count to 10 starting from the variable which is 1. When the loop reaches numbers 3 and seven, I need to echo a statement next to the numbers.

Here is my code:

<?php

    $x = 1;
    while($x <= 10) {
        echo "The number is " . $x . "<br />";
        $x = $x + 1;  // increment by 1 … same as $x++;   
    }


    if ($x = $x + 2) {
        echo "<font color='green'>Third time is a charm</font>";
        //  echo "<p>Third time is a charm</p>";
    } else if ($x = $x + 6) {
        echo "<br>";
        echo "<font color='blue'>You got 7! JACKPOT!</font>";
    }

?>

I'm wondering how I would be able to have the echo output next to the statement. I don't know why my if statements aren't currently working right now?

Answer 1

Your if statements are outside your while loop, $x is only ever '10' (err 11) by the time it reaches your conditionals.

If you don't have to use a 'while' loop, you could achieve this cleaner in a for.

for ($i=0; $i<=10; $i++) {
    //conditionals (I would elaborate, but learning by trial and error is great, don't want to rob you of that)
}

If you need to use a while for assignment reasons, just move the brace immediately before the "if" to the end of your script.. ie,

while {
 if() {
 } elseif() {
 }
}

Good luck!

Answer 2

<?php

    $x = 1;
    while($x <= 10) {
        echo "The number is " . $x . "<br />";

        if ($x == 3) {
            echo "<font color='green'>Third time is a charm</font>";
            //  echo "<p>Third time is a charm</p>";
        } else if ($x == 7) {
            echo "<br>";
            echo "<font color='blue'>You got 7! JACKPOT!</font>";
        }

        $x = $x + 1;  // increment by 1 … same as $x++;   
    }

?>

Answer 3

Try this

<?php

//  $i = 1     : start the counter at 1
//  $i <= 10   : execute until 10 is reached
//  $i++       : increment counter by one
for($i = 1; $i <= 10; $i++) {

echo "The number is " . $i;

  if($i == 3) {
    echo "<font color='green'> Third time is a charm</font>";
  } elseif($i == 7) {
    echo "<font color='blue'> You got 7! JACKPOT!</font>";
  }
   echo "<br />";
}

?>

Play around with for loops. They often come in handy.

Answer 4

Your if statements are outside your while loop. The {} represent a block of code that run based on the condition in the () of your while statement, so you need to put them between the { and the ending } . Try something like this:

<?php
$x=0;

// You can add the increment modifier inside the 
// condition too, which will save you a line of code. (Just a shortcut)
while (++$x <= 10) {
    echo "The number is " . $x . "<br />";

    if ($x == 3) {
        echo "<font color='green'>Third time is a charm</font>";
        //  echo "<p>Third time is a charm</p>";
    } else if ($x == 7) {
        echo "<br>";
        echo "<font color='blue'>You got 7! JACKPOT!</font>";
    }
}
?>

or in a switch: (If you want to handle more than just 3 and 7, a switch would probably be the cleanest way.)

<?php
$x=0;

// You can add the increment modifier inside the 
// condition too, which will save you a line of code. (Just a shortcut)
while (++$x <= 10) {
    echo "The number is " . $x . "<br />";

    switch ($x) {
        case 3:
            echo "<font color='green'>Third time is a charm</font>";
            //  echo "<p>Third time is a charm</p>";
            break;
        case 7:
            echo "<br>";
            echo "<font color='blue'>You got 7! JACKPOT!</font>";
            break;
        default:
            // The default logic goes here.

    }
}    
?>

Make sure you use two equal signs to compare values, as a single equal sign will just assign a value to the variable on the left, with the statement on the right.

$x = 1; // Assignment.

Compared to

$x == 1; // Comparison.

PS $x++ is the same as $x = $x + 1 , just a shorthand way of writing it. If the ++ is before the variable (eg ++$x ), the value will be incremented before the statement is evaluated. If it's after (eg $x++ ), the statement will be evaluated first (eg $x <= 10 ), then the value will be incremented after.

Hope this helps.