1# Obtaining the JSVM API Version Using JSVM-API
2
3## Introduction
4
5This topic walks you through on how to use JSVM-API to obtain the API version and VM information.
6
7## Available APIs
8
9| API                      | Description                      |
10|----------------------------|--------------------------------|
11| OH_JSVM_GetVersion         | Obtains the latest JSVM API version supported by the JSVM runtime. |
12| OH_JSVM_GetVMInfo          | Obtains the VM information.             |
13
14## Example
15
16If you are just starting out with JSVM-API, see [JSVM-API Development Process](use-jsvm-process.md). The following demonstrates only the C++ and ArkTS code related to version management.
17
18### OH_JSVM_GetVersion
19
20Use **OH_JSVM_GetVersion** to obtain the latest JSVM API version supported by the JSVM runtime.
21
22CPP code:
23
24```cpp
25// hello.cpp
26#include "napi/native_api.h"
27#include "ark_runtime/jsvm.h"
28#include <hilog/log.h>
29// Register the GetVersion callback.
30static JSVM_CallbackStruct param[] = {
31    {.data = nullptr, .callback = GetVersion},
32};
33static JSVM_CallbackStruct *method = param;
34// Set a property descriptor named getVersion and associate it with a callback. This allows the GetVersion callback to be called from JS.
35static JSVM_PropertyDescriptor descriptor[] = {
36    {"getVersion", nullptr, method++, nullptr, nullptr, nullptr, JSVM_DEFAULT},
37};
38// Define OH_JSVM_GetVersion.
39static JSVM_Value GetVersion(JSVM_Env env, JSVM_CallbackInfo info)
40{
41    uint32_t jsVersion = 0;
42    // Obtain the latest JSVM API version supported by the current JSVM runtime.
43    JSVM_Status status = OH_JSVM_GetVersion(env, &jsVersion);
44    JSVM_Value result = nullptr;
45    OH_JSVM_CreateUint32(env, jsVersion, &result);
46    int value = static_cast<int>(jsVersion);
47    if (status != JSVM_OK) {
48        OH_LOG_ERROR(LOG_APP, "JSVM GetVersion fail");
49    } else {
50        OH_LOG_INFO(LOG_APP, "JSVM GetVersion success:%{public}d", value);
51    }
52    return result;
53}
54```
55
56ArkTS code:
57
58```ts
59import hilog from "@ohos.hilog"
60// Import the native APIs.
61import napitest from "libentry.so"
62let script: string = `
63    getVersion()
64`;
65try {
66  let result = napitest.runJsVm(script);
67  hilog.info(0x0000, 'testJSVM', 'Test JSVM getVersion: %{public}s', result);
68} catch (error) {
69  hilog.error(0x0000, 'testJSVM', 'Test JSVM getVersion error: %{public}s', error.message);
70}
71```
72
73### OH_JSVM_GetVMInfo
74
75Use **OH_JSVM_GetVMInfo** to obtain VM information.
76
77CPP code:
78
79```cpp
80// hello.cpp
81#include "napi/native_api.h"
82#include "ark_runtime/jsvm.h"
83#include <hilog/log.h>
84// Register the GetVMInfo callback.
85static JSVM_CallbackStruct param[] = {
86    {.data = nullptr, .callback = GetVMInfo},
87};
88static JSVM_CallbackStruct *method = param;
89// Set a property descriptor named GetVMInfo and associate it with a callback. This allows the GetVMInfo callback to be called from JS.
90static JSVM_PropertyDescriptor descriptor[] = {
91    {"getVMInfo", nullptr, method++, nullptr, nullptr, nullptr, JSVM_DEFAULT},
92};
93// Define OH_JSVM_GetVMInfo.
94// Print the JSVM information.
95void PrintVmInfo(JSVM_VMInfo vmInfo) {
96    OH_LOG_INFO(LOG_APP, "JSVM API apiVersion: %{public}d", vmInfo.apiVersion);
97    OH_LOG_INFO(LOG_APP, "JSVM API engine: %{public}s", vmInfo.engine);
98    OH_LOG_INFO(LOG_APP, "JSVM API version: %{public}s", vmInfo.version);
99    OH_LOG_INFO(LOG_APP, "JSVM API cachedDataVersionTag: 0x%{public}x", vmInfo.cachedDataVersionTag);
100}
101static JSVM_Value GetVMInfo(JSVM_Env env, JSVM_CallbackInfo info)
102{
103    // Obtain the VM information.
104    JSVM_VMInfo result;
105    OH_JSVM_GetVMInfo(&result);
106    // Obtain the latest API version supported by the VM and print the information.
107    JSVM_Value version = nullptr;
108    OH_JSVM_CreateUint32(env, result.apiVersion, &version);
109    // Output VM information.
110    PrintVmInfo(result);
111    return version;
112}
113```
114
115ArkTS code:
116
117```ts
118import hilog from "@ohos.hilog"
119// Import the native APIs.
120import napitest from "libentry.so"
121let script: string = `
122    getVMInfo()
123`
124try {
125  let result = napitest.runJsVm(script);
126  hilog.info(0x0000, 'testJSVM', 'Test JSVM getVMInfo apiVersion: %{public}s', result);
127} catch (error) {
128  hilog.error(0x0000, 'testJSVM', 'Test JSVM getVMInfo error: %{public}s', error.message);
129}
130```
131