count_chars

Name:count_chars

Category:String

Programming Language:php

One-line Description:Returns information about the characters used in the string.

Example

Example 1

Returns a string containing all the different characters used in "Hello World!" (Mode 3):

 <span class="token php language-php"><span class="token delimiter important"><?php</span>
<span class="token variable">$str</span> <span class="token operator">=</span> <span class="token string double-quoted-string">"Hello World!"</span> <span class="token punctuation">;</span>
<span class="token keyword">echo</span> <span class="token function">count_chars</span> <span class="token punctuation">(</span> <span class="token variable">$str</span> <span class="token punctuation">,</span> <span class="token number">3</span> <span class="token punctuation">)</span> <span class="token punctuation">;</span>
<span class="token delimiter important">?></span></span>

Try it yourself

Example 2

Returns a string containing all characters that were not used in "Hello World!" (Schema 4):

 <span class="token php language-php"><span class="token delimiter important"><?php</span>
<span class="token variable">$str</span> <span class="token operator">=</span> <span class="token string double-quoted-string">"Hello World!"</span> <span class="token punctuation">;</span>
<span class="token keyword">echo</span> <span class="token function">count_chars</span> <span class="token punctuation">(</span> <span class="token variable">$str</span> <span class="token punctuation">,</span> <span class="token number">4</span> <span class="token punctuation">)</span> <span class="token punctuation">;</span>
<span class="token delimiter important">?></span></span>

Try it yourself

Example 3

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

 <span class="token php language-php"><span class="token delimiter important"><?php</span>
<span class="token variable">$str</span> <span class="token operator">=</span> <span class="token string double-quoted-string">"Hello World!"</span> <span class="token punctuation">;</span>
<span class="token function">print_r</span> <span class="token punctuation">(</span> <span class="token function">count_chars</span> <span class="token punctuation">(</span> <span class="token variable">$str</span> <span class="token punctuation">,</span> <span class="token number">1</span> <span class="token punctuation">)</span> <span class="token punctuation">)</span> <span class="token punctuation">;</span>
<span class="token delimiter important">?></span></span>

Try it yourself

Example 4

Another instance of counting the number of times an ASCII character appears in a string:

 <span class="token php language-php"><span class="token delimiter important"><?php</span>
<span class="token variable">$str</span> <span class="token operator">=</span> <span class="token string double-quoted-string">"PHP is pretty fun!!"</span> <span class="token punctuation">;</span>
<span class="token variable">$strArray</span> <span class="token operator">=</span> <span class="token function">count_chars</span> <span class="token punctuation">(</span> <span class="token variable">$str</span> <span class="token punctuation">,</span> <span class="token number">1</span> <span class="token punctuation">)</span> <span class="token punctuation">;</span>

<span class="token keyword">foreach</span> <span class="token punctuation">(</span> <span class="token variable">$strArray</span> <span class="token keyword">as</span> <span class="token variable">$key</span> <span class="token operator">=></span> <span class="token variable">$value</span> <span class="token punctuation">)</span>
  <span class="token punctuation">{</span>
<span class="token keyword">echo</span> <span class="token string double-quoted-string">"character<b>&#39;"</span> <span class="token operator">.</span> <span class="token function">chr</span> <span class="token punctuation">(</span> <span class="token variable">$key</span> <span class="token punctuation">)</span> <span class="token operator">.</span> <span class="token string double-quoted-string">"&#39;</b> is found <span class="token interpolation"><span class="token variable">$value</span></span> times.<br>"</span> <span class="token punctuation">;</span>
  <span class="token punctuation">}</span>
<span class="token delimiter important">?></span></span>

Try it yourself