title: Japanese Detecting Full-Width characters
body: <p>I need to disallow writing full-width Japanese characters in input field,
  half-width are ok and any other symbols are ok except fullwidth ones.</p>
  
  <p>Here <a href="https://gist.github.com/terrancesnyder/1345094" rel="noreferrer">https://gist.github.com/terrancesnyder/1345094</a>
  I found regex for full-width Katakana (zenkaku 全角) is it enough ?
  Currently my code looks like this</p>
  
  <pre><code>if ( /[ァ-ヶ]/.test("カナ") ) {
    console.log('full width');
  }else{
    console.log('not full width');
  }
  </code></pre>
  
  <p>I'm not familiar with Japanese so I don't know what else I have to check also, I mean they have katakana, hiragana and so on that 's why I'm not sure my script is good enough, please let me know what do you think</p>