Java 如何检查android设备上的wifi或3g网络

在这里，我的android设备支持wifi和3g。在此设备上可用的网络的特定时间。因为我的要求是当3g可用时，我必须上传少量数据。当wifi可用时，必须上传整个数据。所以，我必须检查连接是wifi还是3g。请帮帮我。提前谢谢

我用这个：

/**
 * Checks if we have a valid Internet Connection on the device.
 * @param ctx
 * @return True if device has internet
 *
 * Code from: http://www.androidsnippets.org/snippets/131/
 */
public static boolean haveInternet(Context ctx) {

    NetworkInfo info = (NetworkInfo) ((ConnectivityManager) ctx
            .getSystemService(Context.CONNECTIVITY_SERVICE)).getActiveNetworkInfo();

    if (info == null || !info.isConnected()) {
        return false;
    }
    if (info.isRoaming()) {
        // here is the roaming option you can change it if you want to
        // disable internet while roaming, just return false
        return false;
    }
    return true;
}

你也需要

<uses-permission android:name="android.permission.ACCESS_NETWORK_STATE" />

然后像这样使用它：

if (mobile == NetworkInfo.State.CONNECTED || mobile == NetworkInfo.State.CONNECTING) {
    //mobile
} else if (wifi == NetworkInfo.State.CONNECTED || wifi == NetworkInfo.State.CONNECTING) {
    //wifi
}

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要获取移动网络的类型，我将尝试或

您需要在android清单文件中添加以下权限：

<uses-permission android:name="android.permission.ACCESS_NETWORK_STATE" />

developer.android.com的一些参考资料包括：

---

首先获取对ConnectionManager的引用，然后获取设备的引用。 要使用此服务，您需要访问\网络\状态权限

    ConnectivityManager connManager = (ConnectivityManager) getSystemService(CONNECTIVITY_SERVICE);
    NetworkInfo mWifi = connManager.getNetworkInfo(ConnectivityManager.TYPE_WIFI);
    NetworkInfo mMobile = connManager.getNetworkInfo(ConnectivityManager.TYPE_MOBILE);

    if (mWifi.isAvailable() == true) {
        return "Connected to WiFi";
    } else if (mMobile.isAvailable() == true) {
        return "Connected to Mobile Network";
    } else return "No internet Connection"

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您可以使用此方法检查您的internet连接是2G、3G还是4G：

public String getNetworkClass(Context context) {
    TelephonyManager mTelephonyManager = (TelephonyManager)
        context.getSystemService(Context.TELEPHONY_SERVICE);
    int networkType = mTelephonyManager.getNetworkType();
    switch (networkType) {
        case TelephonyManager.NETWORK_TYPE_GPRS:
        case TelephonyManager.NETWORK_TYPE_EDGE:
        case TelephonyManager.NETWORK_TYPE_CDMA:
        case TelephonyManager.NETWORK_TYPE_1xRTT:
        case TelephonyManager.NETWORK_TYPE_IDEN:
            return "2G";
        case TelephonyManager.NETWORK_TYPE_UMTS:
        case TelephonyManager.NETWORK_TYPE_EVDO_0:
        case TelephonyManager.NETWORK_TYPE_EVDO_A:
        case TelephonyManager.NETWORK_TYPE_HSDPA:
        case TelephonyManager.NETWORK_TYPE_HSUPA:
        case TelephonyManager.NETWORK_TYPE_HSPA:
        case TelephonyManager.NETWORK_TYPE_EVDO_B:
        case TelephonyManager.NETWORK_TYPE_EHRPD:
        case TelephonyManager.NETWORK_TYPE_HSPAP:
            return "3G";
        case TelephonyManager.NETWORK_TYPE_LTE:
            return "4G";
        default:
            return "Unknown";
    }
}

public String getNetworkType(Context context){
    String networkType = null;
    ConnectivityManager connectivityManager = (ConnectivityManager) context.getSystemService(Context.CONNECTIVITY_SERVICE);
    NetworkInfo activeNetwork = connectivityManager.getActiveNetworkInfo();
    if (activeNetwork != null) { // connected to the internet
        if (activeNetwork.getType() == ConnectivityManager.TYPE_WIFI) {
                networkType = "WiFi";
        } else if (activeNetwork.getType() == ConnectivityManager.TYPE_MOBILE) {
            networkType = "Mobile";
        }
    } else {
        // not connected to the internet
    }
    return networkType;
}

使用以下方法，您可以检查互联网是否可用，并了解您是否通过移动网络或WiFi访问互联网：

public String getNetworkClass(Context context) {
    TelephonyManager mTelephonyManager = (TelephonyManager)
        context.getSystemService(Context.TELEPHONY_SERVICE);
    int networkType = mTelephonyManager.getNetworkType();
    switch (networkType) {
        case TelephonyManager.NETWORK_TYPE_GPRS:
        case TelephonyManager.NETWORK_TYPE_EDGE:
        case TelephonyManager.NETWORK_TYPE_CDMA:
        case TelephonyManager.NETWORK_TYPE_1xRTT:
        case TelephonyManager.NETWORK_TYPE_IDEN:
            return "2G";
        case TelephonyManager.NETWORK_TYPE_UMTS:
        case TelephonyManager.NETWORK_TYPE_EVDO_0:
        case TelephonyManager.NETWORK_TYPE_EVDO_A:
        case TelephonyManager.NETWORK_TYPE_HSDPA:
        case TelephonyManager.NETWORK_TYPE_HSUPA:
        case TelephonyManager.NETWORK_TYPE_HSPA:
        case TelephonyManager.NETWORK_TYPE_EVDO_B:
        case TelephonyManager.NETWORK_TYPE_EHRPD:
        case TelephonyManager.NETWORK_TYPE_HSPAP:
            return "3G";
        case TelephonyManager.NETWORK_TYPE_LTE:
            return "4G";
        default:
            return "Unknown";
    }
}

public String getNetworkType(Context context){
    String networkType = null;
    ConnectivityManager connectivityManager = (ConnectivityManager) context.getSystemService(Context.CONNECTIVITY_SERVICE);
    NetworkInfo activeNetwork = connectivityManager.getActiveNetworkInfo();
    if (activeNetwork != null) { // connected to the internet
        if (activeNetwork.getType() == ConnectivityManager.TYPE_WIFI) {
                networkType = "WiFi";
        } else if (activeNetwork.getType() == ConnectivityManager.TYPE_MOBILE) {
            networkType = "Mobile";
        }
    } else {
        // not connected to the internet
    }
    return networkType;
}

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看看@govardhan:+1，我也有这个问题。你得到答案了吗？此链接包含你需要的代码。当我在没有sim卡的平板电脑上使用此代码时，此代码会显示错误。