[Resolved] Code Walk-through

[hbradshaw]

Hello:

I have part of a script which produces a drop down box listing the months of the year.

Can someone walk me through some of the lines for this section of the script? I'm not quite sure about some of the lines.

The portion of the script is below.

My specific question relates to the following lines:

for ($x=1; $x <= count($months); $x++) {
echo"<option value=\"$x\"";
if ($x == $month) {
echo " SELECTED";
}
echo ">".$months[$x-1]."";
}

I know in the first line a counter is being set. The second line will list the options that meet the conditions for the counter.
Line 4....what is this echo " SELECTED"; statement doing? Is it necessary? Where is SELECTED coming from? It's not a defined variable anywhere in the script?

The final echo statement is confusing. I don't understand why you are subracting from from the counter?

Thank you for taking the time to explain this to me.

===========================

$month = $POST['month'];
$year = $POST['year'];

<form method="post" action="<?php echo "$_SERVER[PHP_SELF]"; ?>">
<select name="month">
<?php
$months = Array("January", "February", "March", "April", "May", "June", "July", "August", "September", "October", "November", "December");
for ($x=1; $x <= count($months); $x++) {
echo"<option value=\"$x\"";
if ($x == $month) {
echo " SELECTED";
}
echo ">".$months[$x-1]."";
}
?>
</select>
<select name="year">
<?php
for ($x=1980; $x<=2010; $x++) {
echo "<option";
if ($x == $year) {
echo " SELECTED";
}
echo ">$x";
}
?>
</select>
<input type="submit" value="Go!">
</form>

[kkobashi]

The reference to the SELECTED option determines what is the currently selected item in the list box when it first comes up.

For example, let's say by DEFAULT you want the drop down box to have July set.... it has to be set so something... right? :p

[hbradshaw]

Hi,

Thanks for the reply. The reference to SELECTED makes sense now. I don't know why I didn't see it.

Do you happen to know what this line means?

echo ">".$months[$x-1]."";

First, I'll take a stab at it.

$months = July
$x = July
$x-1 = June

Since July was referenced by the SELECTED echo statement. I think the last echo statement will print all the months that are before July. Am I right or on the right track?

[statusquo]

You may already know a lot of this....but lets look at it section by section.

//$month and $year only have values after the form is submitted
$month = $_POST['month'];
$year = $_POST['year'];

//start the form
<form method="post" action="<?php echo "$_SERVER[PHP_SELF]"; ?>">
<select name="month">
<?php 
//$months[] array starts at 0, Not 1
$months = Array("January", "February", "March", "April", "May", "June", "July", "August", "September", "October", "November", "December"); 
for ($x=1; $x <= count($months); $x++) {
// I am giving the month option a numerical value of x which will be 1 higher than the $months[] array value
// arrays start at 0
// In the first pass of <option value=\"x\""; X will equal 1
echo"<option value=\"$x\"";

// if x is equal to the posted month, the month option will be selected in the form 
if ($x == $month) { 
echo " SELECTED"; 
}

// in the first pass of echo ">".$months[$x-1].""; January will be 
// displayed because 1-1 = 0 and $months[0] = January 
echo ">".$months[$x-1].""; 
} 
?> 
</select> 
<select name="year"> 
<?php 
for ($x=1980; $x<=2010; $x++) { 
echo "<option"; 
if ($x == $year) { 
echo " SELECTED"; 
} 
echo ">$x"; 
} 
?> 
</select> 
<input type="submit" value="Go!"> 
</form>

[hbradshaw]

Hi,

Thanks for the reply. Now it makes sense.

My last question, I'm wondering if it is possible to select a month and have the calendar automatically show that month. Right now, you have to click the Go button. Is it possible to do this?

[statusquo]

javascript is very good for that, but I know nothing about javascript.

[hbradshaw]

Hi,

I'm not a JavaScript person either. I guess I'll have to chat with that forum.

Thanks for the reply.