I use this
function getBrowserName() {
var name = "Unknown";
if(navigator.userAgent.indexOf("MSIE")!=-1){
name = "MSIE";
}
else if(navigator.userAgent.indexOf("Firefox")!=-1){
name = "Firefox";
}
else if(navigator.userAgent.indexOf("Opera")!=-1){
name = "Opera";
}
else if(navigator.userAgent.indexOf("Chrome") != -1){
name = "Chrome";
}
else if(navigator.userAgent.indexOf("Safari")!=-1){
name = "Safari";
}
return name;
}
if( getBrowserName() == "Safari" ){
alert("You are using Safari");
}else{
alert("You are surfing on " + getBrowserName(name));
}