判断android网络是否可用

public boolean isNetworkAvailable() {
		Context context = getApplicationContext();
		ConnectivityManager connectivity = (ConnectivityManager) context
				.getSystemService(context.CONNECTIVITY_SERVICE);
		if (connectivity == null) {
		} else {
			NetworkInfo[] info = connectivity.getAllNetworkInfo();
			if (info != null) {
				for (int i = 0; i < info.length; i++) {
					if (info[i].getState() == NetworkInfo.State.CONNECTED) {
						return true;
					}
				}
			}
		}
		return false;
	}

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使用方法

if (!isNetworkAvailable()) {
					System.out.println("没有网络连接");
				} else {
					System.out.println("网络连接可用");
				}