Notification.permission

Notification 的只读属性 permission 用来表明用户是否允许当前域显示Web Notification. 

Syntax

var permission = Notification.permission;

Value

permission 的类型为 DOMString . 该属性的可能值为:

• granted: 用户已经明确的授予了显示通知的权限。.
• denied: 用户已经明确的拒绝了显示通知的权限。
• default: 用户还未被询问是否授权; 这种情况下权限将视为 denied.

Examples

下面的代码片段详细的说明了，当你首次检查浏览器是否支持Notification，然后检查当前域是否被授予了发送Notification的权限，并且在发送一个通知前进行请求的用法．

function notifyMe() {
  // Let's check if the browser supports notifications
  if (!("Notification" in window)) {
    console.log("This browser does not support desktop notification");
  }

  // Let's check whether notification permissions have alredy been granted
  else if (Notification.permission === "granted") {
    // If it's okay let's create a notification
    var notification = new Notification("Hi there!");
  }

  // Otherwise, we need to ask the user for permission
  else if (Notification.permission !== 'denied' || Notification.permission === "default") {
    Notification.requestPermission(function (permission) {
      // If the user accepts, let's create a notification
      if (permission === "granted") {
        var notification = new Notification("Hi there!");
      }
    });
  }

  // At last, if the user has denied notifications, and you 
  // want to be respectful there is no need to bother them any more.
}

Specifications

Browser compatibility

We're converting our compatibility data into a machine-readable JSON format. This compatibility table still uses the old format, because we haven't yet converted the data it contains. Find out how you can help!

Firefox OS notes

Chrome notes

Safari notes

See also

• Using the Notifications API
• Permissions API