Variable values can change over the course of a script.
Here're some important things to know about variables: In the above example we have created two variables where first one has assigned with a string value and the second has assigned with a number.
You can also use double quotes inside without escaping them. It should be defined in its on line at the beginning of the string and at the end.
The example below illustrates how the Heredoc method is used to create string values. Note: you can use anything you like in place of EOT Output: The Nowdoc string creation method is similar to the heredoc method but works like the way single quotes work. Nowdoc is ideal when working with raw data that do not need to be parsed.
And then we display it, and free memory of every string.
Note that we forgot the hash value (if it were computed before, no need to think about that detail). Like we already said, the hash is used if the is used as part of Hash Tables.
You manage to collect the user input in an array called $form: Almost every editor (even VIM) will break the syntax highlighting on the case where you have two forward slashes in a string. In fact, you are likely to have tons of that because of URLs.
In Example #8, above, consider the risk to the script if a programmer were to define('koolaid1', 'XYZ'); For this reason it's wise to use quotes around literal-string associative array keys.
Interned strings also interact with OPCache extension. When used with OPCache, they also get recycled from request to request. What you tend to do is simply create a new string “foo”: But a question arises : Hasn’t that piece of string already been created before you need it?
When you need a string, you code is executed at some point in PHP’s life, that means that some piece of code happening before yours may have needed the exact same piece of string (“foo” for our example).