A string variable is used to store and manipulate a piece of text.
Strings in PHP
- String variables are used for values that contain character strings.
- After we create a string we can manipulate it. A string can be used directly in a function or it can be stored in a variable.
- Below, the PHP script assigns the string “Hello World” to a string variable called $txt:
| <?php $txt=”Hello World”; echo $txt; ?> |
The output of the code above will be:
| Hello World |
Now, lets try to use some different functions and operators to manipulate our string
The Concatenation Operator
- There is only one string operator in PHP.
- The concatenation operator (.) is used to put two string values together.
- To concatenate two variables together, use the dot (.) operator:
| <?php $txt1=”Hello World”; $txt2=”1234″; echo $txt1 . ” ” . $txt2; ?> |
The output of the code above will be:
| Hello World 1234 |
- If we look at the code above you see that we used the concatenation operator two times. This is because we had to insert a third string.
Between the two string variables we added a string with a single
character, an empty space, to separate the two variables.
Using the strlen() function
- The strlen() function is used to find the length of a string.
- Let’s find the length of our string “Hello world!”:
| <?php echo strlen(“Hello world!”); ?> |
The output of the code above will be:
| 12 |
- The length of a string is often used in loops or other functions, when it is important to know when the string ends. (i.e. in a loop, we would want to stop the loop after the last character in the string)
Using the strpos() function
- The strpos() function is used to search for a string or character within a string.
- If a match is found in the string, this function will return the position of the first match. If no match is found, it will return FALSE.
- Let’s see if we can find the string “world” in our string:
| <?php echo strpos(“Hello world!”,”world”); ?> |
The output of the code above will be:
| 6 |
As you see the position of the string “world” in our string is position 6. The reason that it is 6, and not 7, is that the first position in the string is 0, and not 1.