How to get a variable from a file to another file in Node js

Question

Here is my first file  var self   this  var config          confvar    configval      I want this configuration variable in another file  so I have done this in another file  conf   require    conf    url   conf config confvar   But it gives me an error   TypeError  Cannot read property  confvar  of undefined  What can I do

User · Answer

File FileOne js  module exports     ClientIDUnsplash    SuperSecretKey       File FileTwo js  var   ClientIDUnsplash     require    FileOne     This example works best for React

User · Answer

You need module exports   Exports An object which is shared between all instances of the current module and made accessible through require    exports is the same as the module exports object  See src node js for more information  exports isn t actually a global but rather local to each module   For example  if you would like to expose variableName with value  quot variableValue quot  on sourceFile js then you can either set the entire exports as such  module exports     variableName   quot variableValue quot      Or you can set the individual value with  module exports variableName    quot variableValue quot    To consume that value in another file  you need to require      it first  with relative pathing   const sourceFile   require    sourceFile    console log sourceFile variableName    Alternatively  you can deconstruct it  const   variableName     require    sourceFile                  current directory --             would be one directory down            is two directories down  If all you want out of the file is variableName then   sourceFile js  const variableName    variableValue  module exports   variableName    consumer js  const variableName   require    sourceFile    Edit  2020   Since Node js version 8 9 0  you can also use ECMAScript Modules with varying levels of support  The documentation   For Node v13 9 0 and beyond  experimental modules are enabled by default For versions of Node less than version 13 9 0  use --experimental-modules   Node js will treat the following as ES modules when passed to node as the initial input  or when referenced by import statements within ES module code     Files ending in  mjs     Files ending in  js when the nearest parent package json file contains a top-level field  quot type quot  with a value of  quot module quot   Strings passed in as an argument to --eval or --print  or piped to node via STDIN  with the flag --input-type module   Once you have it setup  you can use import and export  Using the example above  there are two approaches you can take   sourceFile js     This is a named export of variableName export const variableName    variableValue     Alternatively  you could have exported it as a default      For sake of explanation  I m wrapping the variable in an object    but it is not necessary      You can actually omit declaring what variableName is here        variableName   is equivalent to   variableName  variableName   in this case   export default   variableName  variableName       consumer js     There are three ways of importing      If you need access to a non-default export  then     you use   nameOfExportedVariable    import   variableName   from    sourceFile  console log variableName      variableValue      Otherwise  you simply provide a local variable name     for what was exported as default  import sourceFile from    sourceFile  console log sourceFile variableName      variableValue     sourceFileWithoutDefault js     The third way of importing is for situations where there    isn t a default export but you want to warehouse everything    under a single variable  Say you have  export const a    A  export const b    B     consumer2 js    Then you can import all exports under a single variable    with the usage of   as  import   as sourceFileWithoutDefault from    sourceFileWithoutDefault   console log sourceFileWithoutDefault a      A  console log sourceFileWithoutDefault b      B      You can use this approach even if there is a default export  import   as sourceFile from    sourceFile      Default exports are under the variable default  console log sourceFile default       variableName   variableValue        As well as named exports  console log sourceFile variableName      variableValue

[node.js] How to get a variable from a file to another file in Node.js

The answer is

File FileOne.js:

File FileTwo.js:

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