React-router中结合webpack实现按需加载实例

require.ensure(["module-a", "module-b"], function() {
 var a = require("module-a");
 // ...
});

 output: {
    path: __dirname + '/dist/js/',
    publicPath:'/js/',
    filename: '[name].js',
    chunkFilename: '[name].[chunkhash:5].chunk.js'
  },

export const routes={
 path:'/',
 getComponent(nextState,callback){
  require.ensure([],require=>{
   callback(null,require('../ponents/nav').default);
  },'nav');
 },
 indexRoute:{
  getComponent(nextState,callback){
   require.ensure([],require=>{
    callback(null,require('../ponents/examine').default);
   },'examine');
  }
 },
 childRoutes:[{
  path:'examine',
  getComponent(nextState,callback){
   require.ensure([],require=>{
    callback(null,require('../ponents/examine').default);
   },'examine');
   }
 },
 {
  path:'admin',
  getComponent(nextState,callback){
   require.ensure([],require=>{
    callback(null,require('../ponents/admin').default);
   },'admin');
  }
 },
 {
  path:'history',
  getComponent(nextState,callback){
   require.ensure([],require=>{
    callback(null,require('../ponents/history').default);
   },'history');
  }
 },
 {
  path:'feedback',
  getComponent(nextState,callback){
   require.ensure([],require=>{
    callback(null,require('../ponents/feedback').default);
   },'feedback')
  }
 }
]
};