System Parameter
NOTE
- The initial APIs of this module are supported since API version 6. Newly added APIs will be marked with a superscript to indicate their earliest API version.
- This is a system API and cannot be called by third-party applications.
Modules to Import
import parameter from '@ohos.systemParameter'
parameter.getSync
getSync(key: string, def?: string): string
Obtains the value of the attribute with the specified key.
System capability: SystemCapability.Startup.SysInfo
Parameters
Name | Type | Mandatory | Description |
---|---|---|---|
key | string | Yes | Key of the system attribute. |
def | string | No | Default Value |
Return value
Type | Description |
---|---|
string | System attribute value. If the specified key does not exist, the default value is returned. If no default value has been set, an empty string will be returned. |
Example
try {
var info = parameter.getSync("test.parameter.key");
console.log(JSON.stringify(info));
}catch(e){
console.log("getSync unexpected error: " + e);
}
parameter.get
get(key: string, callback: AsyncCallback<string>): void
Obtains the value of the attribute with the specified key. This API uses an asynchronous callback to return the result.
System capability: SystemCapability.Startup.SysInfo
Parameters
Name | Type | Mandatory | Description |
---|---|---|---|
key | string | Yes | Key of the system attribute. |
callback | AsyncCallback<string> | Yes | Callback used to return the result. |
Example
try {
parameter.get("test.parameter.key", function (err, data) {
if (err == undefined) {
console.log("get test.parameter.key value success:" + data)
} else {
console.log(" get test.parameter.key value err:" + err.code)
}});
}catch(e){
console.log("get unexpected error: " + e);
}
parameter.get
get(key: string, def: string, callback: AsyncCallback<string>): void
Obtains the value of the attribute with the specified key. This API uses an asynchronous callback to return the result.
System capability: SystemCapability.Startup.SysInfo
Parameters
Name | Type | Mandatory | Description |
---|---|---|---|
key | string | Yes | Key of the system attribute. |
def | string | Yes | Default Value |
callback | AsyncCallback<string> | Yes | Callback used to return the result. |
Example
try {
parameter.get("test.parameter.key", "default", function (err, data) {
if (err == undefined) {
console.log("get test.parameter.key value success:" + data)
} else {
console.log(" get test.parameter.key value err:" + err.code)
}
});
}catch(e){
console.log("get unexpected error:" + e)
}
parameter.get
get(key: string, def?: string): Promise<string>
Obtains the value of the attribute with the specified key. This API uses a promise to return the result.
System capability: SystemCapability.Startup.SysInfo
Parameters
Name | Type | Mandatory | Description |
---|---|---|---|
key | string | Yes | Key of the system attribute. |
def | string | No | Default Value |
Return value
Type | Description |
---|---|
Promise<string> | Promise used to return the execution result. |
Example
try {
var p = parameter.get("test.parameter.key");
p.then(function (value) {
console.log("get test.parameter.key success: " + value);
}).catch(function (err) {
console.log("get test.parameter.key error: " + err.code);
});
}catch(e){
console.log("get unexpected error: " + e);
}
parameter.setSync
setSync(key: string, value: string): void
Sets a value for the attribute with the specified key.
System capability: SystemCapability.Startup.SysInfo
Parameters
Name | Type | Mandatory | Description |
---|---|---|---|
key | string | Yes | Key of the system attribute. |
value | string | Yes | System attribute value to set. |
Example
try {
parameter.setSync("test.parameter.key", "default");
}catch(e){
console.log("set unexpected error: " + e);
}
parameter.set(key: string, value: string, callback: AsyncCallback<void>)
set(key: string, value: string, callback: AsyncCallback<void>): void
Sets a value for the attribute with the specified key. This API uses an asynchronous callback to return the result.
System capability: SystemCapability.Startup.SysInfo
Parameters
Name | Type | Mandatory | Description |
---|---|---|---|
key | string | Yes | Key of the system attribute. |
def | string | Yes | Default Value |
callback | AsyncCallback<void> | Yes | Callback used to return the result. |
Example
try {
parameter.set("test.parameter.key", "testValue", function (err, data) {
if (err == undefined) {
console.log("set test.parameter.key value success :" + data)
} else {
console.log("set test.parameter.key value err:" + err.code)
}});
}catch(e){
console.log("set unexpected error: " + e);
}
parameter.set(key: string, def?: string)
set(key: string, def?: string): Promise<string>
Sets a value for the attribute with the specified key. This API uses a promise to return the result.
System capability: SystemCapability.Startup.SysInfo
Parameters
Name | Type | Mandatory | Description |
---|---|---|---|
key | string | Yes | Key of the system attribute. |
def | string | No | Default Value |
Return value
Type | Description |
---|---|
Promise<string> | Promise used to return the execution result. |
Example
try {
var p = para.set("test.parameter.key", "testValue");
p.then(function (value) {
console.log("set test.parameter.key success: " + value);
}).catch(function (err) {
console.log(" set test.parameter.key error: " + err.code);
});
}catch(e){
console.log("set unexpected error: " + e);
}