vm.runInThisContext(code[, options])

• code <string> 要编译和运行的 JavaScript 代码。

  ¥code <string> The JavaScript code to compile and run.

• options <Object> | <string>

  • filename <string> 指定此脚本生成的堆栈跟踪中使用的文件名。默认值：'evalmachine.<anonymous>'。

    ¥filename <string> Specifies the filename used in stack traces produced by this script. Default: 'evalmachine.<anonymous>'.

  • lineOffset <number> 指定在此脚本生成的堆栈跟踪中显示的行号偏移量。默认值：0。

    ¥lineOffset <number> Specifies the line number offset that is displayed in stack traces produced by this script. Default: 0.

  • columnOffset <number> 指定在此脚本生成的堆栈跟踪中显示的第一行列号偏移量。默认值：0。

    ¥columnOffset <number> Specifies the first-line column number offset that is displayed in stack traces produced by this script. Default: 0.

  • displayErrors <boolean> 当为 true 时，如果编译 code 时出现 Error，则导致错误的代码行会附加到堆栈跟踪中。默认值：true。

    ¥displayErrors <boolean> When true, if an Error occurs while compiling the code, the line of code causing the error is attached to the stack trace. Default: true.

  • timeout <integer> 指定终止执行前执行 code 的毫秒数。如果执行终止，则将抛出 Error。此值必须是严格的正整数。

    ¥timeout <integer> Specifies the number of milliseconds to execute code before terminating execution. If execution is terminated, an Error will be thrown. This value must be a strictly positive integer.

  • breakOnSigint <boolean> 如果是 true，接收 SIGINT（Ctrl+C）将终止执行并抛出 Error。已通过 process.on('SIGINT') 附加的事件的现有句柄在脚本执行期间被禁用，但在此之后继续工作。默认值：false。

    ¥breakOnSigint <boolean> If true, receiving SIGINT (Ctrl+C) will terminate execution and throw an Error. Existing handlers for the event that have been attached via process.on('SIGINT') are disabled during script execution, but continue to work after that. Default: false.

  • cachedData <Buffer> | <TypedArray> | <DataView> 为所提供的源提供可选的 Buffer 或 TypedArray 或 DataView，其中包含 V8 的代码缓存数据。

    ¥cachedData <Buffer> | <TypedArray> | <DataView> Provides an optional Buffer or TypedArray, or DataView with V8's code cache data for the supplied source.

  • importModuleDynamically <Function> | <vm.constants.USE_MAIN_CONTEXT_DEFAULT_LOADER> 用于指定在调用 import() 时评估此脚本期间应如何加载模块。此选项是实验模块 API 的一部分。不建议在生产环境中使用它。详细信息参见 编译 API 中支持动态 import()。

    ¥importModuleDynamically <Function> | <vm.constants.USE_MAIN_CONTEXT_DEFAULT_LOADER> Used to specify the how the modules should be loaded during the evaluation of this script when import() is called. This option is part of the experimental modules API. We do not recommend using it in a production environment. For detailed information, see Support of dynamic import() in compilation APIs.

• 返回：<any> 脚本中最后一条语句执行的结果。

  ¥Returns: <any> the result of the very last statement executed in the script.

vm.runInThisContext() 编译 code，在当前 global 的上下文中运行它并返回结果。运行代码无权访问局部作用域，但可以访问当前 global 对象。

¥vm.runInThisContext() compiles code, runs it within the context of the current global and returns the result. Running code does not have access to local scope, but does have access to the current global object.

如果 options 是字符串，则指定文件名。

¥If options is a string, then it specifies the filename.

以下示例说明使用 vm.runInThisContext() 和 JavaScript eval() 函数来运行相同的代码：

¥The following example illustrates using both vm.runInThisContext() and the JavaScript eval() function to run the same code:

const vm = require('node:vm');
let localVar = 'initial value';

const vmResult = vm.runInThisContext('localVar = "vm";');
console.log(`vmResult: '${vmResult}', localVar: '${localVar}'`);
// Prints: vmResult: 'vm', localVar: 'initial value'

const evalResult = eval('localVar = "eval";');
console.log(`evalResult: '${evalResult}', localVar: '${localVar}'`);
// Prints: evalResult: 'eval', localVar: 'eval' 拷贝

因为 vm.runInThisContext() 无权访问本地作用域，所以 localVar 不变。相比之下，eval() 确实可以访问本地范围，因此更改了 localVar 的值。这样 vm.runInThisContext() 很像 间接 eval() 调用，例如 (0,eval)('code')。

¥Because vm.runInThisContext() does not have access to the local scope, localVar is unchanged. In contrast, eval() does have access to the local scope, so the value localVar is changed. In this way vm.runInThisContext() is much like an indirect eval() call, e.g. (0,eval)('code').