script.runInNewContext([contextObject[, options]])

• contextObject <Object> 将被上下文隔离化的对象。 如果为 undefined，则将创建新的对象。
• options <Object>
  • 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。
  • 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。
  • breakOnSigint <boolean> 如果为 true，则接收 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。
  • contextName <string> 新创建的上下文的可读名称。 默认值: 'VM Context i', 其中 i 是创建的上下文的升序数字索引。
  • contextOrigin <string> 对应于新创建的用于显示目的的上下文的来源。 来源的格式应该像 URL，但只有协议、主机和端口（如果需要），就像 URL 对象的 url.origin 属性的值。 最值得注意的是，该字符串应省略尾部斜杠，因为它表示路径。 默认值: ''。
  • contextCodeGeneration <Object>
    • strings <boolean> 如果设置为 false，则任何对 eval 或函数构造函数（Function、GeneratorFunction 等）的调用都将抛出 EvalError。 默认值: true。
    • wasm <boolean> 如果设置为 false，则任何编译 WebAssembly 模块的尝试都将抛出 WebAssembly.CompileError。 默认值: true。
  • microtaskMode <string> 如果设置为 afterEvaluate，则微任务（通过 Promise 和 async function 调度的任务）将在脚本运行后立即运行。 在这种情况下，它们包含在 timeout 和 breakOnSigint 范围内。
• 返回: <any> 脚本中执行的最后一条语句的结果。

首先对给定的 contextObject 进行上下文隔离化，在创建的上下文中运行 vm.Script 对象包含的编译代码，并返回结果。 运行代码无权访问本地作用域。

以下示例编译设置全局变量的代码，然后在不同的上下文中多次执行代码。 全局变量设置并包含在每个单独的 context 中。

const vm = require('vm');

const script = new vm.Script('globalVar = "set"');

const contexts = [{}, {}, {}];
contexts.forEach((context) => {
  script.runInNewContext(context);
});

console.log(contexts);
// 打印: [{ globalVar: 'set' }, { globalVar: 'set' }, { globalVar: 'set' }]

• contextObject <Object> An object that will be contextified. If undefined, a new object will be created.
• options <Object>
  • 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> 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> 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.
  • contextName <string> Human-readable name of the newly created context. Default: 'VM Context i', where i is an ascending numerical index of the created context.
  • contextOrigin <string> Origin corresponding to the newly created context for display purposes. The origin should be formatted like a URL, but with only the scheme, host, and port (if necessary), like the value of the url.origin property of a URL object. Most notably, this string should omit the trailing slash, as that denotes a path. Default: ''.
  • contextCodeGeneration <Object>
    • strings <boolean> If set to false any calls to eval or function constructors (Function, GeneratorFunction, etc) will throw an EvalError. Default: true.
    • wasm <boolean> If set to false any attempt to compile a WebAssembly module will throw a WebAssembly.CompileError. Default: true.
  • microtaskMode <string> If set to afterEvaluate, microtasks (tasks scheduled through Promises and async functions) will be run immediately after the script has run. They are included in the timeout and breakOnSigint scopes in that case.
• Returns: <any> the result of the very last statement executed in the script.

First contextifies the given contextObject, runs the compiled code contained by the vm.Script object within the created context, and returns the result. Running code does not have access to local scope.

The following example compiles code that sets a global variable, then executes the code multiple times in different contexts. The globals are set on and contained within each individual context.

const vm = require('vm');

const script = new vm.Script('globalVar = "set"');

const contexts = [{}, {}, {}];
contexts.forEach((context) => {
  script.runInNewContext(context);
});

console.log(contexts);
// Prints: [{ globalVar: 'set' }, { globalVar: 'set' }, { globalVar: 'set' }]