webpack not able to import images( using express a

问题:

I am not able to import images in my headercomponent.ts. I suspect it is because of something i am doing wrong while compiling ts(using webpack ts loader) because same thing works with react( where the components are written in es6)

The error location is

//headercomponent.ts
import {Component, View} from "angular2/core";
import {ROUTER_DIRECTIVES, Router} from "angular2/router";
import {AuthService} from "../../services/auth/auth.service";
import logoSource from "../../images/logo.png"; //**THIS CAUSES ERROR**  Cannot find module '../../images/logo.png'

@Component({
    selector: 'my-header',
    //templateUrl:'components/header/header.tmpl.html' ,
    template: `<header class="main-header">
  <div class="top-bar">
    <div class="top-bar-title">
      <a href="/"><img src="{{logoSource}}"></a>
    </div>

my webpack config is

// webpack.config.js
'use strict';

var path = require('path');
var autoprefixer = require('autoprefixer');
var webpack = require('webpack');
var ExtractTextPlugin = require('extract-text-webpack-plugin');
var basePath = path.join(__dirname,'public');
//const TARGET = process.env.npm_lifecycle_event;
console.log("bp " + basePath)
module.exports = {
  entry: path.join(basePath,'/components/boot/boot.ts'),
  output: {
    path: path.join(basePath,"..","/build"), // This is where images AND js will go
    publicPath: path.join(basePath,"..","/build/assets"),
   // publicPath: path.join(basePath ,'/images'), // This is used to generate URLs to e.g. images
    filename: 'bundle.js'
  },
  plugins: [
    new ExtractTextPlugin("bundle.css")
  ],
  module: {
    preLoaders: [ { test: /\.tsx$/, loader: "tslint" } ],
    //
    loaders: [
      { test: /\.(png!jpg)$/, loader: 'file-loader?name=/img/[name].[ext]'  }, // inline base64 for <=8k images, direct URLs for the rest
      {
        test: /\.json/,
        loader: 'json-loader',
      },
      {
        test: /\.ts$/,
        loader: 'ts-loader',
        exclude: [/node_modules/]
      },
      {
        test: /\.js$/,
        loader: 'babel-loader'
      },
      {
        test: /\.scss$/,
        exclude: [/node_modules/],
        loader: ExtractTextPlugin.extract("style", "css!postcss!sass?outputStyle=expanded")
      },
      // fonts and svg
      { test: /\.woff(\?v=\d+\.\d+\.\d+)?$/, loader: "url-loader?limit=10000&mimetype=application/font-woff" },
      { test: /\.woff2(\?v=\d+\.\d+\.\d+)?$/, loader: "url-loader?limit=10000&mimetype=application/font-woff" },
      { test: /\.ttf(\?v=\d+\.\d+\.\d+)?$/, loader: "url-loader?limit=10000&mimetype=application/octet-stream" },
      { test: /\.eot(\?v=\d+\.\d+\.\d+)?$/, loader: "file" },
      { test: /\.svg(\?v=\d+\.\d+\.\d+)?$/, loader: "url-loader?limit=10000&mimetype=image/svg+xml" }
    ]
  },
  resolve: {
    // now require('file') instead of require('file.coffee')
    extensions: ['', '.ts', '.webpack.js', '.web.js', '.js', '.json', 'es6', 'png']
  },
  devtool: 'source-map'
};

and my directory structure looks like this

-/
 -server/
 -build/
 -node-modules/
 -public/
  -components/
   -boot/
    -boot.component.ts
   -header/
    -header.component.ts
  -images/
   -logo.png
  -services/
-typings/
 -browser/
 -main/
 -browser.d.ts
 -main.d.ts
-tsconfig.json
-typings.json

my tsconfig file is as follows:

 //tsconfig.json
     {
      "compilerOptions": {
        "target": "es5",
        "sourceMap": true,
        "emitDecoratorMetadata": true,
        "experimentalDecorators": true,
        "removeComments": false,
        "noImplicitAny": false
      },
      "exclude": [
        "node_modules"
      ]
    }

I suspect I am messing some thing in typescript compilation , not sure what

回答1:

The problem is that you confuse TypeScript level modules and Webpack level modules.

In Webpack any file that you import goes through some build pipeline.

In Typescript only .ts and .js files are relevant and if you try to import x from file.png TypeScript just does not know what to do with it, Webpack config is not used by TypeScript.

In your case you need to separate the concerns, use import from for TypeScript/EcmaScript code and use require for Webpack specifics.

You would need to make TypeScript ignore this special Webpack require syntax with a definition like this in a .d.ts file:

declare function require(string): string;

This will make TypeScript ignore the require statements and Webpack will be able to process it in the build pipeline.

回答2:

Instead of:

import image from 'pathToImage/image.extension';

Use:

const image = require('pathToImage/image.extension');

回答3:

I'm using

import * as myImage from 'path/of/my/image.png';

and created a typescript definition with

declare module "*.png" {
    const value: any;
    export = value;
}

This only works when you have a correct handler like the file-loader in webpack. Because this handler will give you a path to your file.

回答4:

I also had same issue so I used following approach:

import * as myImage from 'path/of/my/image';

In my component I simply assigned the imported image to a data member;

export class TempComponent{
    public tempImage = myImage;
}

and used it in template as:

<img [src]="tempImage" alt="blah blah blah">

回答5:

A small improvement to Christian Stornowski's answer would be to make the export default, i.e.

declare module "*.png" {
  const value: string;
  export default value;
}

So you can import an image using:

import myImg from 'img/myImg.png';

回答6:

If you want to use the ES6 syntax for importing.

First be sure that in your tsconfig.json you have:

target: 'es5',
module: 'es6'

The following should now work:

import MyImage from './images/my-image.png';

回答7:

To be able to use default import like this:

import grumpyCat from '../assets/grumpy_cat.jpg';

Define jpg module declaration:

declare module "*.jpg" {
const value: string;
  export default value;
}

and in your tsconfig use "module": "es6" (see @vedran comment above) or when you use "module": "commonjs" add "esModuleInterop": true,

  "compilerOptions": {
    "module": "commonjs",
    "target": "es5",
    "esModuleInterop": true,
...

Source: https://github.com/TypeStrong/ts-loader/issues/344#issuecomment-381398818