在此页

• 句法
• 异常
• 范例
• 规范
• 浏览器兼容性
• 相关话题

安全上下文
此特征只可用于 安全上下文 (HTTPS)，在某些或所有 支持浏览器 .

这是 实验性技术
检查 浏览器兼容性表格 要小心谨慎在生产中使用这之前。

getAvailability() 方法为 蓝牙 interface of Web Bluetooth API interface exposes the Bluetooth capabilities of the current device. For a returns a 布尔 which is true if the deveice has a Bluetooth adapter and false otherwise (unless user configured User Agent not to expose a real value).

注意： User might not allow use of Web Bluetooth API, even if getAvailability() 返回 true ( navigator.bluetooth.requestDevice() might not resolve with a BluetoothDevice ). Also, user can configure User Agent to return a fixed value instead of a real one.

句法

var readerPromise = Bluetooth.getAvailability();
					

参数

None.

返回值

A Promise that resolves with 布尔 .

异常

This method doesn't throw any exceptions.

范例

The following snippet prints out a message in the console specifying wheter or not Bluetooth is supported:

navigator.bluetooth.getAvailability().then(available => {
  if (available)
      console.log("This device supports Bluetooth!");
  else
      console.log("Doh! Bluetooth is not supported");
});
					

规范

规范	状态	注释
Web Bluetooth The definition of 'getAvailability()' in that specification.	草案	初始定义。

浏览器兼容性

The compatibility table on this page is generated from structured data. If you'd like to contribute to the data, please check out https://github.com/mdn/browser-compat-data and send us a pull request. 更新 GitHub 上的兼容性数据

	桌面						移动
	Chrome	Edge	Firefox	Internet Explorer	Opera	Safari	Android webview	Chrome for Android	Firefox for Android	Opera for Android	Safari on iOS	Samsung Internet
getAvailability	Chrome 56 注意事项 56 注意事项 macOS only. 56 注意事项 Disabled Linux and versions of Windows earlier than 10. Disabled From version 56: this feature is behind the #enable-experimental-web-platform-features preference (needs to be set to enabled ). To change preferences in Chrome, visit chrome://flags. 70 注意事项 Windows 10.	Edge ≤79 注意事项 ≤79 注意事项 macOS only. ≤79 注意事项 Disabled Linux and versions of Windows earlier than 10. Disabled From version ≤79: this feature is behind the #enable-experimental-web-platform-features preference (needs to be set to enabled ). ≤79 注意事项 Windows 10.	Firefox 不支持 No	IE 不支持 No	Opera 43 注意事项 43 注意事项 macOS only. 43 注意事项 Disabled Linux and versions of Windows earlier than 10. Disabled From version 43: this feature is behind the #enable-experimental-web-platform-features preference (needs to be set to enabled ). 57 注意事项 Windows 10.	Safari 不支持 No	WebView Android 不支持 No	Chrome Android 56	Firefox Android 不支持 No	Opera Android 43	Safari iOS 不支持 No	Samsung Internet Android 6.0

图例

完整支持

完整支持

不支持

不支持

实验。期望将来行为有所改变。

实验。期望将来行为有所改变。

见实现注意事项。

用户必须明确启用此特征。

用户必须明确启用此特征。

元数据

• 最后修改： Jun 13, 2020

相关话题

1. Web Bluetooth API
2. 蓝牙
3. 方法

   1. requestDevice()
4. Related pages for Bluetooth API

   1. BluetoothAdvertisingData
   2. BluetoothDevice
   3. BluetoothGATTCharacteristic
   4. BluetoothGATTDescriptor
   5. BluetoothGATTRemoteServer
   6. BluetoothGATTService