title: How can I check a string for multiple certain characters?
body: <p>I have a string and I need to check it for several characters. I can do that with <code>strpos();</code>. But in this case, I would need to use <code>strpose();</code> several times. something like this:</p>
  
  <pre><code>$str = 'this is a test';
  if(
     strpos($str, "-") === false &amp;&amp;
     strpos($str, "_") === false &amp;&amp;
     strpos($str, "@") === false &amp;&amp;
     strpos($str, "/") === false &amp;&amp;
     strpos($str, "'") === false &amp;&amp;
     strpos($str, "]") === false &amp;&amp;
     strpos($str, "[") === false &amp;&amp;
     strpos($str, "#") === false &amp;&amp;
     strpos($str, "&amp;") === false &amp;&amp;
     strpos($str, "*") === false &amp;&amp;
     strpos($str, "^") === false &amp;&amp;
     strpos($str, "!") === false &amp;&amp;
     strpos($str, "?") === false &amp;&amp;
     strpos($str, "{") === false &amp;&amp;
     strpos($str, "}") === false 
    )
      { do stuff }
  </code></pre>
  
  <p>Now I want to know, is it possible to use a <code>regex</code> to define my condition summary?</p>
  
  <hr>
  
  <p><strong>Edit:</strong> here is some examples:</p>
  
  <pre><code>$str = 'foo'     ----I want this output---&gt; true
  $str = 'foo!'    -------------------------&gt; false
  $str = '}foo'    -------------------------&gt; false
  $str = 'foo*bar' -------------------------&gt; false
  </code></pre>
  
  <p>and so on. In other word, I want just text character: <code>abcdefghi...</code> .</p>