使用typeof或instanceof:

const assert = require('assert');

function myFunction(Date myDate, String myString)
{
    assert( typeof(myString) === 'string',  'Error message about incorrect arg type');
    assert( myDate instanceof Date,         'Error message about incorrect arg type');
}

您可以在函数中使用包装器来实现自动处理类型检查的系统。

使用这种方法，您可以构建一个完整的声明式类型检查系统，该系统将为您管理类型检查。 如果您有兴趣更深入地了解这个概念，请查看Functyped库

下面的实现以一种简单但有效的方式说明了主要思想:

/* * checkType() : Test the type of the value. If succeds return true, * if fails, throw an Error */ function checkType(value,type, i){ // perform the appropiate test to the passed // value according to the provided type switch(type){ case Boolean : if(typeof value === 'boolean') return true; break; case String : if(typeof value === 'string') return true; break; case Number : if(typeof value === 'number') return true; break; default : throw new Error(`TypeError : Unknown type provided in argument ${i+1}`); } // test didn't succeed , throw error throw new Error(`TypeError : Expecting a ${type.name} in argument ${i+1}`); } /* * typedFunction() : Constructor that returns a wrapper * to handle each function call, performing automatic * arguments type checking */ function typedFunction( parameterTypes, func ){ // types definitions and function parameters // count must match if(parameterTypes.length !== func.length) throw new Error(`Function has ${func.length} arguments, but type definition has ${parameterTypes.length}`); // return the wrapper... return function(...args){ // provided arguments count must match types // definitions count if(parameterTypes.length !== args.length) throw new Error(`Function expects ${func.length} arguments, instead ${args.length} found.`); // iterate each argument value, and perform a // type check against it, using the type definitions // provided in the construction stage for(let i=0; i<args.length;i++) checkType( args[i], parameterTypes[i] , i) // if no error has been thrown, type check succeed // execute function! return func(...args); } } // Play time! // Declare a function that expects 2 Numbers let myFunc = typedFunction( [ Number, Number ], (a,b)=>{ return a+b; }); // call the function, with an invalid second argument myFunc(123, '456') // ERROR! Uncaught Error: TypeError : Expecting a Number in argument 2

我假设您允许IDE帮助您;那么下面的答案可能会帮助你。

IDE: jetbrains/Golang如果你的IDE不是这个也没关系。我相信所有支持JSDoc的IDE都能满足您的大部分需求。

它可以很好地显示JSDoc。

Demo

我的- pkg base64编码- js。

/**
 * Convert string to the base64 format.
 *
 * @param str {string} Input string
 * @returns {string} some message about return...
 * @example
 *  - btoa(toBinary("☸☹☺☻☼☾☿"))
 *  - Str2base64("☸☹☺☻☼☾☿")
 * @see https://developer.mozilla.org/en-US/docs/Web/API/WindowOrWorkerGlobalScope/btoa#unicode_strings
 */
export function Str2base64(str) {
  return btoa(toBinary(str))
}

. js

import * as base64 from "../pkg/encoding/base64"
const filenameB64 = base64.Str2base64("test")

有用的JSDoc文档

JSDoc块标签 显示@returns， @param， @type…

其他链接

jetbrains JSDoc /评论

不，JavaScript不是静态类型语言。有时可能需要手动检查函数体中的参数类型。

虽然不能将类型通知JavaScript语言，但可以通知IDE，因此可以获得更有用的自动补全。

这里有两种方法:

Use JSDoc, a system for documenting JavaScript code in comments. In particular, you'll need the @param directive: /** * @param {Date} myDate - The date * @param {string} myString - The string */ function myFunction(myDate, myString) { // ... } You can also use JSDoc to define custom types and specify those in @param directives, but note that JSDoc won't do any type checking; it's only a documentation tool. To check types defined in JSDoc, look into TypeScript, which can parse JSDoc tags. Use type hinting by specifying the type right before the parameter in a /* comment */: This is a pretty widespread technique, used by ReactJS for instance. Very handy for parameters of callbacks passed to 3rd party libraries.

打印稿

对于实际的类型检查，最接近的解决方案是使用TypeScript，它是JavaScript的超集。这里是5分钟内的TypeScript。

不，相反，你需要根据你的需要做这样的事情:

function myFunction(myDate, myString) {
  if(arguments.length > 1 && typeof(Date.parse(myDate)) == "number" && typeof(myString) == "string") {
    //Code here
  }
}