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POPHP - having a hard time understading why a certain value is echoed. Can an assignment take place inside of if and executed in else?
 

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  1. POPHP - having a hard time understading why a certain value is echoed. Can an assignment take place inside of if and executed in else?
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    <p>Hy to everyone ! Please excuse my ignorance, I'm so new to php.</p> <p>I have a hard time understanding why a php code behaves in that way. The code is working but I'm so clueless about why those values are echoed.</p> <p>(The code has been simplified for explanation purposes but it would normally populate and format a table based on a custom number of columns)</p> <p><strong><em></strong> QUESTION *</em>** (see the code)</p> <p>Why does the variable <code>$cell</code> echo (see: ?????? QUESTION ?????): 1 2 3 4 5 6 7 ? I was expecting 0 1 2 3 4 5 6 // because I thought the starting point for it would be $cell = 0, as assigned at the start. The only rational reason would be that it inherits its value from $cell +=$i (from the for loop), but when the case is $col=2 isn't the first statement skipped entirely and only the else statement executed? </p> <pre><code>&lt;?php for ($i=1; $i &lt;= 7 ; $i++) { $cell = 0; echo "&lt;tr&gt;"; for ($col=1; $col &lt;= 2; $col++) { echo "&lt;td&gt;" ; if ($col == 1) { echo $cell; // echoes: 0 0 0 0 0 0 0 ----&gt; because $cell = 0 $cell +=$i; echo $cell; // echoes: 1 2 3 4 5 6 7 ----&gt; because of $cell +=$i; } else { echo $cell ; // echoes: 1 2 3 4 5 6 7 ?????? QUESTION ????? $cell +=7; echo $cell; // echoes: 8 9 10 11 12 13 14 } echo "&lt;/td&gt;"; } echo "&lt;/tr&gt;"; } ?&gt; </code></pre> <p>Any help would be gratefully appreciated. </p>
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    1. USJonah Bishop
    1. USSevrotic
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    1. COWhy did you write such a convoluted loop interaction? Just use the two output blocks verbatim, instead of for($col) and if($col). -- Regarding your question title, this is how PHPs variable scope works. You are accessing the same variable in both the if and the else.
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    2. COBecause he's new to programming...
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    3. COSo the $cell +=$i in the if loop is not lost/ignored when the if condition is false, it just carries its value through the rest of the code. Right ?
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      1. USSevrotic
 

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