PHP introduced a deprecation warning in version 7.4.0 about using braces {} to access offsets in arrays and strings. This means that while versions prior to PHP 7.4 may still support this syntax, in PHP 7.4 and later, PHP will issue a deprecation warning when you use braces to access offsets in an array or string. In future versions of PHP (PHP 8.0 and above, this syntax may no longer be supported and may cause runtime errors), this syntax may be completely removed, causing runtime errors.
To follow best practices and ensure code maintainability and future compatibility, it is recommended to use square brackets [] instead of curly brackets {} to access array and string offsets.
For example, the previous code using braces:
$array = array('name' => 'John');
echo $array{'name'}; // Use braces to access array elements
$string = 'hello';
echo $string{1}; // Use braces to access string characters
should be updated to code using square brackets:
$array = ['name' => 'John'];
echo $array['name']; // Use square brackets to access array elements
$string = 'hello';
echo $string[1]; // Use square brackets to access string characters