Setting the Selected Item in a Drop-Down Box
In web development, the
Consider the following scenario: you have a database that stores a month value, and you want to create an edit page that allows users to modify this month. You'll need a drop-down box prepopulated with the current month from the database.
Solution:
To set the selected item in the drop-down, assign the 'selected' attribute to the appropriate
<option value="January" selected="selected">January</option>
PHP Implementation:
To dynamically set the selected item based on the database value, use the following PHP code:
<option value="January" <?=$row['month'] == 'January' ? ' selected="selected"' : '';?>>January</option>
This code checks if the current month in the database is 'January' and adds the 'selected="selected"' attribute accordingly.
Alternate Approach:
An alternative approach is to create an array of values and iterate over it to generate the drop-down options. This can result in a cleaner and more maintainable code:
<?php
$months = ['January', 'February', 'March', 'April', 'May', 'June'];
echo '<select>';
foreach ($months as $month) {
$selected = $month == $row['month'] ? ' selected="selected"' : '';
echo "<option value='$month'$selected>$month</option>";
}
echo '</select>';
?>
By using this method, you can easily add or remove months from the drop-down without modifying the PHP code.
The above is the detailed content of How to Preselect an Item in a HTML Drop-Down Box?. For more information, please follow other related articles on the PHP Chinese website!
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