wap浏览自动跳转到wap页面的js代码

function is_mobile() {
    var regex_match = /(nokia|iphone|android|motorola|^mot-|softbank|foma|docomo|kddi|up.browser|up.link|htc|dopod|blazer|netfront|helio|hosin|huawei|novarra|CoolPad|webos|techfaith|palmsource|blackberry|alcatel|amoi|ktouch|nexian|samsung|^sam-|s[cg]h|^lge|ericsson|philips|sagem|wellcom|bunjalloo|maui|symbian|smartphone|midp|wap|phone|windows ce|iemobile|^spice|^bird|^zte-|longcos|pantech|gionee|^sie-|portalmmm|jigs browser|hiptop|^benq|haier|^lct|operas*mobi|opera*mini|320x320|240x320|176x220)/i;
  var u = navigator.userAgent;
  if (null == u) {
   return true;
  }
  var result = regex_match.exec(u);

  if (null == result) {
   return false
  } else {
   return true
  }
 }
 if (is_mobile()) {
  document.location.href= '/wap';
 }