相关疑难解决方法(0)

我需要能够在运行时合并两个(非常简单的)JavaScript对象.例如,我想:

var obj1 = { food: 'pizza', car: 'ford' }
var obj2 = { animal: 'dog' }

obj1.merge(obj2);

//obj1 now has three properties: food, car, and animal

有没有人有这个脚本或知道内置的方法来做到这一点？我不需要递归,我不需要合并函数,只需要平面对象上的方法.

在JavaScript中比较对象的最佳方法是什么？

例:

var user1 = {name : "nerd", org: "dev"};
var user2 = {name : "nerd", org: "dev"};
var eq = user1 == user2;
alert(eq); // gives false

我知道如果它们引用完全相同的对象,则两个对象是相等的,但有没有办法检查它们是否具有相同的属性值？

以下方式对我有用,但这是唯一的可能性吗？

var eq = Object.toJSON(user1) == Object.toJSON(user2);
alert(eq); // gives true

严格的相等运算符将告诉您两个对象类型是否相等.但是,有没有办法判断两个对象是否相等,就像 Java中的哈希码值一样？

Stack Overflow问题JavaScript中是否有任何类型的hashCode函数？类似于这个问题,但需要更多的学术答案.上面的场景说明了为什么需要有一个,我想知道是否有任何等效的解决方案.

我很难尝试导入lodash模块.我使用npm + gulp设置我的项目,并继续击中同一面墙.我尝试过常规的lodash,还有lodash-es.

lodash npm包:(包根文件夹中有一个index.js文件)

import * as _ from 'lodash';    

结果是:

error TS2307: Cannot find module 'lodash'.

lodash-es npm包:(在lodash.js中有一个defaut导出我的包根文件夹)

import * as _ from 'lodash-es/lodash';

结果是:

error TS2307: Cannot find module 'lodash-es'.   

gulp任务和webstorm都报告了同样的问题.

有趣的是,这不会返回错误:

import 'lodash-es/lodash';

......但当然没有"_"......

我的tsconfig.json文件:

{
  "compilerOptions": {
    "target": "es5",
    "module": "system",
    "moduleResolution": "node",
    "sourceMap": true,
    "emitDecoratorMetadata": true,
    "experimentalDecorators": true,
    "removeComments": false,
    "noImplicitAny": false
  },
  "exclude": [
    "node_modules"
  ]
}

我的gulpfile.js:

var gulp = require('gulp'),
    ts = require('gulp-typescript'),
    uglify = require('gulp-uglify'),
    sourcemaps = require('gulp-sourcemaps'),
    tsPath = …

我有这个间隔,它执行ajax请求,目前每5秒.我对if声明有疑问.我的代码总是输入它,两个json值完全相同,为什么它们看起来不同？

var newActivity = null, oldActivity = null;
setInterval(function(){
    $.ajax({
        type: "get",
        url: "/get/new_activity",
        dataType: "json",
        success: function(data){
            oldActivity = newActivity;
            newActivity = data;
            console.log(JSON.stringify(oldActivity));
            console.log(JSON.stringify(newActivity));
            if(JSON.stringify(oldActivity) != JSON.stringify(newActivity)){
                $("#new-activity").slideDown( "fast" );
            }
        }
    });
}, 5000);

编辑
这是控制台输出(虚线是分开请求,它不在实际输出中)

null
[{"title":"How many planets are in the solar system?","title_url":"How-many-planets-are-in-the-solar-system%3F","id":"2","answers":"1","asked":"2013-01-11 10:03:50","asked_pretty":"Today","activity":"2013-01-11 12:33:53","activity_pretty":"Today"},{"title":"Why is the sky blue?","title_url":"Why-is-the-sky-blue%3F","id":"1","answers":"1","asked":"2013-01-11 09:55:13","asked_pretty":"Today","activity":"2013-01-11 12:03:45","activity_pretty":"Today"}]

---------------------------------------------------

[{"title":"How many planets are in the solar system?","title_url":"How-many-planets-are-in-the-solar-system%3F","id":"2","answers":"1","asked":"2013-01-11 10:03:50","asked_pretty":"Today","activity":"2013-01-11 12:33:53","activity_pretty":"Today"},{"title":"Why is the sky blue?","title_url":"Why-is-the-sky-blue%3F","id":"1","answers":"1","asked":"2013-01-11 09:55:13","asked_pretty":"Today","activity":"2013-01-11 12:03:45","activity_pretty":"Today"}]
[{"title":"How many planets are in …