97 lines
2.6 KiB
Markdown
97 lines
2.6 KiB
Markdown
---
|
|
title: Strings
|
|
---
|
|
## Strings
|
|
|
|
A string is series of characters. These can be used to store any textual information in your application.
|
|
|
|
There are a number of different ways to create strings in PHP.
|
|
|
|
### Single Quotes
|
|
|
|
Simple strings can be created using single quotes.
|
|
```PHP
|
|
$name = 'Joe';
|
|
```
|
|
|
|
To include a single quote in the string, use a backslash to escape it.
|
|
|
|
```PHP
|
|
$last_name = 'O\'Brian';
|
|
```
|
|
|
|
|
|
### Double Quotes
|
|
|
|
You can also create strings using double quotes.
|
|
```PHP
|
|
$name = "Joe";
|
|
```
|
|
|
|
To include a double quote, use a backslash to escape it.
|
|
|
|
```PHP
|
|
$quote = "Mary said, \"I want some toast,\" and then ran away.";
|
|
```
|
|
|
|
Double quoted strings also allow escape sequences. These are special codes that put characters in your string that represent typically invisible characters. Examples include newlines `\n`, tabs `\t`, and actual backslashes `\\`.
|
|
|
|
You can also embed PHP variables in double quoted strings to have their values added to the string.
|
|
```PHP
|
|
$name = 'Joe';
|
|
$greeting = "Hello $name"; // now contains the string "Hello Joe"
|
|
```
|
|
|
|
|
|
### PHP String Functions
|
|
In this chapter we will look at some commonly used functions to manipulate strings.
|
|
|
|
#### Get The Length of a String
|
|
The PHP strlen() function returns the length of a string.
|
|
The example below returns the length of the string "Hello world!":
|
|
````
|
|
<?php
|
|
echo strlen("Hello world!"); // outputs 12
|
|
?>
|
|
````
|
|
A string is series of characters.
|
|
PHP only supports a 256-character set and hence does not offer native Unicode support.
|
|
|
|
#### Count The Number of Words in a String
|
|
The PHP str_word_count() function counts the number of words in a string:
|
|
````
|
|
<?php
|
|
echo str_word_count("Hello world!"); // outputs 2
|
|
?>
|
|
````
|
|
|
|
#### Reverse a String
|
|
The PHP strrev() function reverses a string:
|
|
````
|
|
<?php
|
|
echo strrev("Hello world!"); // outputs !dlrow olleH
|
|
?>
|
|
````
|
|
|
|
#### Search For a Specific Text Within a String
|
|
The PHP strpos() function searches for a specific text within a string.
|
|
If a match is found, the function returns the character position of the first match. If no match is found, it will return FALSE.
|
|
The example below searches for the text "world" in the string "Hello world!":
|
|
````
|
|
<?php
|
|
echo strpos("Hello world!", "world"); // outputs 6
|
|
?>
|
|
````
|
|
|
|
#### Replace Text Within a String
|
|
````
|
|
<?php
|
|
echo str_replace("world", "Dolly", "Hello world!"); // outputs Hello Dolly!
|
|
?>
|
|
````
|
|
|
|
### More Information:
|
|
<!-- Please add any articles you think might be helpful to read before writing the article -->
|
|
* [PHP: Strings](http://php.net/manual/en/language.types.string.php)
|
|
* [PHP String tutorial](https://www.w3schools.com/php/php_string.asp)
|