1# Cellular Data<a name="EN-US_TOPIC_0000001105538940"></a>
2
3-   [Introduction](#section117mcpsimp)
4-   [Directory Structure](#section121mcpsimp)
5-   [Constraints](#section125mcpsimp)
6-   [Available APIs](#section131mcpsimp)
7-   [Usage Guidelines](#section160mcpsimp)
8    -   [Checking the Cellular Data Status](#section192mcpsimp)
9    -   [Obtaining the Cellular Data Status](#section213mcpsimp)
10    -   [Check if cellular mobile data service is enabled](#section234mcpsimp)
11    -   [Check if cellular data roaming is enabled](#section255mcpsimp)
12
13-   [Repositories Involved](#section234mcpsimp)
14
15## Introduction<a name="section117mcpsimp"></a>
16
17The cellular data module is a tailorable component of the Telephony subsystem. It depends on the telephony core service \(core\_service\) and RIL Adapter \(ril\_adapter\). The module provides functions such as cellular data activation, cellular data fault detection and rectification, cellular data status management, cellular data switch management, cellular data roaming management, APN management, and network management and interaction.
18
19**Figure  1**  Architecture of the cellular data module<a name="fig332493822512"></a>
20![](figures/en-us_architecture-of-the-cellular-data-module.png)
21
22## Directory Structure<a name="section121mcpsimp"></a>
23
24```
25base/telephony/cellular_data/
26├── figures
27├── frameworks
28│   ├── js
29│   │   └── napi
30│   │       ├── include                  #  js head files
31│   │       └── src                      #  js source files
32│   └── native
33├── interfaces                           # externally exposed interface
34│   ├── innerkits
35│   └── kits
36│       └── js
37│           └── declaration              # external JS API interfaces
38├── sa_profile                           # SA profiles
39├── services
40│   ├── include                          # head files
41│   │   ├── apn_manager
42│   │   ├── common
43│   │   ├── state_machine
44│   │   └── utils
45│   └── src                              # source files
46│       ├── apn_manager
47│       ├── state_machine
48│       └── utils
49└── test
50    └── unit_test                        # unit test code
51
52```
53
54## Constraints<a name="section125mcpsimp"></a>
55
56-   Programming language: JavaScript
57-   In terms of software, this module needs to work with the telephony core service \(core\_service\) and RIL Adapter \(call\_manger\).
58-   In terms of hardware, the accommodating device must be equipped with a modem and a SIM card capable of independent cellular communication.
59
60## Available APIs<a name="section131mcpsimp"></a>
61
62**Table  1**  External APIs provided by the cellular data module
63
64<a name="table133mcpsimp"></a>
65
66| API                                                          | Description                                                  | Required Permission              |
67| ------------------------------------------------------------ | ------------------------------------------------------------ | -------------------------------- |
68| function isCellularDataEnabled(callback: AsyncCallback\<boolean>): void; | Checks whether the cellular data is enabled                  | ohos.permission.GET_NETWORK_INFO |
69| function getCellularDataState(callback: AsyncCallback\<DataConnectState>): void; | Obtains the cellular data status.                            | ohos.permission.GET_NETWORK_INFO |
70| function isCellularDataEnabledSync(): boolean;               | Checks if cellular mobile data service is enabled.           | ohos.permission.GET_NETWORK_INFO |
71| function isCellularDataRoamingEnabledSync(slotId: number): boolean; | Checks if cellular data roaming is enabled（The parameter slotId is the SIM card id, 0 represents card one, and 1 represents card two）. | ohos.permission.GET_NETWORK_INFO |
72
73
74## Usage Guidelines<a name="section160mcpsimp"></a>
75
76### Checking the Cellular Data Status<a name="section192mcpsimp"></a>
77
781.  Call the  **IsCellularDataEnabled**  method in callback or Promise mode to check whether the cellular data is enabled.
792.  This method works in asynchronous mode. The execution result is returned through the callback.
80
81    ```
82    import data from "@ohos.telephony.data";
83
84    // Call the API in callback mode.
85    data.isCellularDataEnabled((err, value) => {
86      if (err) {
87        // If the API call failed, err is not empty.
88        console.error(`failed to isCellularDataEnabled because ${err.message}`);
89        return;
90      }
91      // If the API call succeeded, err is empty.
92      console.log(`success to isCellularDataEnabled: ${value}`);
93    });
94
95    // Call the API in Promise mode.
96    let promise = data.isCellularDataEnabled();
97    promise.then((value) => {
98      // The API call succeeded.
99      console.log(`success to isCellularDataEnabled: ${value}`);
100    }).catch((err) => {
101      // The API call failed.
102      console.error(`failed to isCellularDataEnabled because ${err.message}`);
103    });
104    ```
105
106### Check if cellular mobile data service is enabled<a name="section234mcpsimp"></a>
107
1081. You can determine if cellular data services are enabled by calling isCellularDataEnabledSync.
109
1102. This interface is synchronous, and the relevant execution results will be returned from isCellularDataEnabledSync.
111
112   ```
113   import data from "@ohos.telephony.data";
114
115   try {
116   	// Call the interface [Sync method]
117   	let isEnabled: boolean = data.isCellularDataEnabledSync();
118   	// Call the interface successfully
119       console.log(`isCellularDataEnabledSync success : ${isEnabled}`);
120   } catch (error) {
121   	// Call the interface failed
122       console.log(`isCellularDataEnabledSync failed`);
123   }
124   ```
125
126### Check if cellular data roaming is enabled<a name="section255mcpsimp"></a>
127
1281. You can determine if cellular data roaming services are enabled by calling isCellularDataRoamingEnabledSync.
129
1302. This interface is synchronous, and the relevant execution results will be returned from isCellularDataRoamingEnabledSync.
131
132   ```
133   import data from "@ohos.telephony.data";
134
135   try {
136   	// Call the interface [Sync method]
137   	let isEnabled: boolean = data.isCellularDataRoamingEnabledSync(0);
138   	// Call the interface successfully
139       console.log(`isCellularDataRoamingEnabledSync success : ${isEnabled}`);
140   } catch (error) {
141   	// Call the interface failed
142       console.log(`isCellularDataRoamingEnabledSync failed`);
143   }
144   ```
145
146### Obtaining the Cellular Data Status<a name="section213mcpsimp"></a>
147
148**Table  2**  Description of DataConnectState enum values
149
150<a name="table21531410101919"></a>
151
152| Name                    | ValueDescription |              |
153| ----------------------- | ---------------- | ------------ |
154| DATA_STATE_UNKNOWN      | -1               | Unknown      |
155| DATA_STATE_DISCONNECTED | 0                | Disconnected |
156| DATA_STATE_CONNECTING   | 1                | Connecting   |
157| DATA_STATE_CONNECTED    | 2                | Connected    |
158| DATA_STATE_SUSPENDED    | 3                | Suspended    |
159
160
1611.  Call the  **getCellularDataState**  method in callback or Promise mode to obtain the cellular data status.
1622.  This method works in asynchronous mode. The execution result is returned through the callback.
163
164    ```
165    import data from "@ohos.telephony.data";
166
167    // Call the API in callback mode.
168    data.getCellularDataState((err, value) => {
169      if (err) {
170        // If the API call failed, err is not empty.
171        console.error(`failed to getCellularDataState because ${err.message}`);
172        return;
173      }
174      // If the API call succeeded, err is empty.
175      console.log(`success to getCellularDataState: ${value}`);
176    });
177
178    // Call the API in Promise mode.
179    let promise = data.getCellularDataState();
180    promise.then((value) => {
181      // The API call succeeded.
182      console.log(`success to getCellularDataState: ${value}`);
183    }).catch((err) => {
184      // The API call failed.
185      console.error(`failed to getCellularDataState because ${err.message}`);
186    });
187    ```
188
189
190## Repositories Involved<a name="section234mcpsimp"></a>
191
192Telephony
193
194telephony_cellular_data
195
196telephony_core_service
197
198telephony_ril_adapter
199