title: Blank spaces in regular expression
body: <p>I use this regular to validate many of the input fields of my java web app:</p>
  
  <pre><code>"^[a-zA-Z0-9]+$"
  </code></pre>
  
  <p>But i need to modify it, because i have a couple of fields that need to allow blank spaces(for example: Address).</p>
  
  <p>How can i modify it to allow blank spaces(<strong>if possible not at the start</strong>).</p>
  
  <p>I think i need to use some scape character like <code>\</code></p>
  
  <p>I tried a few different combinations but none of them worked. Can somebody help me with this regex?</p>