PHP BUDDY

Phone Validate in js

function validatephone(xxxxx) {
  var maintainplus = '';
  var numval = xxxxx.value
  if ( numval.charAt(0)=='+' ){ var maintainplus = '+';}
  curphonevar = numval.replace(/[\\A-Za-z!"£$%^&*+_={};:'@#~,¦\/<>?|`¬\]\[]/g,'');
  xxxxx.value = maintainplus + curphonevar;
  var maintainplus = '';
  xxxxx.focus;
}