js：判断是什么浏览器

function browserRedirect() {
  var sUserAgent = navigator.userAgent.toLowerCase();
  var bIsIpad = sUserAgent.match(/ipad/i) == "ipad";
  var bIsIphoneOs = sUserAgent.match(/iphone os/i) == "iphone os";
  var bIsMidp = sUserAgent.match(/midp/i) == "midp";
  var bIsUc7 = sUserAgent.match(/rv:1.2.3.4/i) == "rv:1.2.3.4";
  var bIsUc = sUserAgent.match(/ucweb/i) == "ucweb";
  var bIsAndroid = sUserAgent.match(/android/i) == "android";
  var bIsCE = sUserAgent.match(/windows ce/i) == "windows ce";
  var bIsWM = sUserAgent.match(/windows mobile/i) == "windows mobile";
  var bIsWx = sUserAgent.match(/MicroMessenger/i) == "micromessenger";
  document.writeln("您的浏览设备为：");
  if (bIsWx){
    document.writeln("微信");
  }else if (bIsIpad) {
    document.writeln("pad");
  }else if (bIsIphoneOs || bIsMidp || bIsUc7 || bIsUc || bIsAndroid || bIsCE || bIsWM) {
    document.writeln("phone");
  }else{
    document.writeln("pc");
  }
}

browserRedirect();