php function Count_chars () returns all information for a string

Instance

Returns a string that contains all the different characters used in "Hello world!" (Mode 3):

<?php$str = "Hello world!"; Echo Count_chars ($STR, 3);? >

Definition and usage

The Count_chars () function returns information about the characters used in the string (for example, the number of times an ASCII character appears in a string, or whether a character has been used in a string).

Grammar

Count_chars (String,mode)

Parameter description

string is required. Specifies the string to check.

mode is optional. Specifies the return mode. The default is 0. There are the following different return modes:

0-Array, ASCII value is the key name, the number of occurrences is the key value

1-Array, ASCII value is the key name, the number of occurrences is a key value, only the number of occurrences greater than 0 is listed

2-Array, ASCII value is the key name, the number of occurrences is a key value, only the number of occurrences equal to 0 is listed

3-string with all the different characters used

4-A string with all the different characters that have not been used

Technical details

Return value: Depends on the specified mode parameter.

PHP version: 4+

More examples

Example 1

Returns a string containing all characters not used in "Hello world!" (Mode 4):

<?php$str = "Hello world!"; Echo Count_chars ($STR, 4);? >

Example 2

In this example, we will use Count_chars () to check the string, with the return mode set to 1. Mode 1 Returns an array with the ASCII value as the key name and the number of occurrences of the key value:

<?php$str = "Hello world!"; Print_r (Count_chars ($STR, 1));? >

Example 3

Counts the number of times an ASCII character appears in a string another instance:

<?php$str = "PHP is pretty fun!!"; $strArray = Count_chars ($str, 1), foreach ($strArray as $key + $value) {echo "the character <b>". Chr ($key). " </b> was found $value time (s) <br> ";}?" >

Count_chars instances

<?php$data  =  "Both Ts and one F."; foreach (Count_chars ($data,  1) as  $i  = +  $val) {   Echo  "There were  $val  instance (s) of" "  ,  chr ($i),  " \ "in the String.<br/>";}? >

Operation Result:

There were 4 instance (s) of "" in the string. There were 1 instance (s) of "." In the string. There were 1 instance (s) of "F" in the string. There were 2 instance (s) of "T" in the string. There were 1 instance (s) of "a" in the string. There were 1 instance (s) of "D" in the string. There were 1 instance (s) of "E" in the string. There were 2 instance (s) of "n" in the string. There were 2 instance (s) of "O" in the string. There were 1 instance (s) of "s" in the string. There were 1 instance (s) of "W" in the string.