js 实现手机振动

//判断手机是否支持
var supportsVibrate = "vibrate" in navigator;


//alert("support vibrate : " + supportsVibrate);


var vibrateInterval;
//duration 震动的时长
function startVibrate(duration) {
//navigator.vibrate(duration);

//if phone support navigator.vibrate
        if (navigator.vibrate) {
            //vibrate 1 second
            navigator.vibrate(duration);
        } else if (navigator.webkitVibrate) {
            navigator.webkitVibrate(duration);
        }
}
// Stops vibration
function stopVibrate() {
// Clear interval and stop persistent vibrating 
if(vibrateInterval) clearInterval(vibrateInterval);
navigator.vibrate(0);
}
// Start persistent vibration at given duration and interval
// Assumes a number value is given
function startPeristentVibrate(duration, interval) {
vibrateInterval = setInterval(function() {
startVibrate(duration);
}, interval);
}


startPeristentVibrate(500,2000);