如何将JavaScript对象转换为字符串?

例子:

var o = {a:1, b:2}
console.log(o)
console.log('Item: ' + o)

输出:

对象{a=1, b=2} //非常好的可读输出:) Item: [object object] //不知道里面有什么:(


当前回答

这里没有一个解决方案对我有效。JSON。stringify似乎是很多人所说的,但它削减了函数,并且在我测试时尝试的一些对象和数组似乎很坏。

我做了自己的解决方案,至少在Chrome中工作。把它贴在这里,这样任何在谷歌上看到的人都能找到它。

//Make an object a string that evaluates to an equivalent object
//  Note that eval() seems tricky and sometimes you have to do
//  something like eval("a = " + yourString), then use the value
//  of a.
//
//  Also this leaves extra commas after everything, but JavaScript
//  ignores them.
function convertToText(obj) {
    //create an array that will later be joined into a string.
    var string = [];

    //is object
    //    Both arrays and objects seem to return "object"
    //    when typeof(obj) is applied to them. So instead
    //    I am checking to see if they have the property
    //    join, which normal objects don't have but
    //    arrays do.
    if (typeof(obj) == "object" && (obj.join == undefined)) {
        string.push("{");
        for (prop in obj) {
            string.push(prop, ": ", convertToText(obj[prop]), ",");
        };
        string.push("}");

    //is array
    } else if (typeof(obj) == "object" && !(obj.join == undefined)) {
        string.push("[")
        for(prop in obj) {
            string.push(convertToText(obj[prop]), ",");
        }
        string.push("]")

    //is function
    } else if (typeof(obj) == "function") {
        string.push(obj.toString())

    //all other values can be done with JSON.stringify
    } else {
        string.push(JSON.stringify(obj))
    }

    return string.join("")
}

编辑:我知道这段代码可以改进,但只是从来没有做过。用户andrey在评论中提出了一个改进:

这里有一点变化的代码,它可以处理'null'和'undefined',也没有添加过多的逗号。

使用它在你自己的风险,因为我没有验证它在所有。请随意提出任何额外的改进意见。

其他回答

请不要使用此答案,因为它只在某些版本的Firefox中有效。没有其他浏览器支持它。使用加里钱伯斯解决方案。

toSource()是您正在寻找的函数,它将以JSON的形式写入。

var object = {};
object.first = "test";
object.second = "test2";
alert(object.toSource());

我希望这个例子将有助于所有那些谁都在数组对象的工作

var data_array = [{
                    "id": "0",
                    "store": "ABC"
                },{
                    "id":"1",
                    "store":"XYZ"
                }];
console.log(String(data_array[1]["id"]+data_array[1]["store"]));
setobjToString:function(obj){
        var me =this;
        obj=obj[0];
        var tabjson=[];
        for (var p in obj) {
            if (obj.hasOwnProperty(p)) {
                if (obj[p] instanceof Array){
                    tabjson.push('"'+p +'"'+ ':' + me.setobjToString(obj[p]));
                }else{
                    tabjson.push('"'+p +'"'+':"'+obj[p]+'"');
                }
            }
        }  tabjson.push()
        return '{'+tabjson.join(',')+'}';
    }
function objToString (obj) {
    var str = '{';
    if(typeof obj=='object')
      {

        for (var p in obj) {
          if (obj.hasOwnProperty(p)) {
              str += p + ':' + objToString (obj[p]) + ',';
          }
      }
    }
      else
      {
         if(typeof obj=='string')
          {
            return '"'+obj+'"';
          }
          else
          {
            return obj+'';
          }
      }



    return str.substring(0,str.length-1)+"}";
}

循环引用

通过使用下面的替换器,我们可以产生更少冗余的JSON -如果源对象包含对某个对象的多次引用,或者包含循环引用-那么我们通过特殊的路径字符串(类似于JSONPath)引用它-我们如下所示

let s = JSON.stringify(obj, refReplacer());

function refReplacer() { let m = new Map(), v= new Map(), init = null; return function(field, value) { let p= m.get(this) + (Array.isArray(this) ? `[${field}]` : '.' + field); let isComplex= value===Object(value) if (isComplex) m.set(value, p); let pp = v.get(value)||''; let path = p.replace(/undefined\.\.?/,''); let val = pp ? `#REF:${pp[0]=='[' ? '$':'$.'}${pp}` : value; !init ? (init=value) : (val===init ? val="#REF:$" : 0); if(!pp && isComplex) v.set(value, path); return val; } } // --------------- // TEST // --------------- // gen obj with duplicate references let a = { a1: 1, a2: 2 }; let b = { b1: 3, b2: "4" }; let obj = { o1: { o2: a }, b, a }; // duplicate reference a.a3 = [1,2,b]; // circular reference b.b3 = a; // circular reference let s = JSON.stringify(obj, refReplacer(), 4); console.log(s);

奖励:这里是这种序列化的逆函数

function parseRefJSON(json) { let objToPath = new Map(); let pathToObj = new Map(); let o = JSON.parse(json); let traverse = (parent, field) => { let obj = parent; let path = '#REF:$'; if (field !== undefined) { obj = parent[field]; path = objToPath.get(parent) + (Array.isArray(parent) ? `[${field}]` : `${field?'.'+field:''}`); } objToPath.set(obj, path); pathToObj.set(path, obj); let ref = pathToObj.get(obj); if (ref) parent[field] = ref; for (let f in obj) if (obj === Object(obj)) traverse(obj, f); } traverse(o); return o; } // ------------ // TEST // ------------ let s = `{ "o1": { "o2": { "a1": 1, "a2": 2, "a3": [ 1, 2, { "b1": 3, "b2": "4", "b3": "#REF:$.o1.o2" } ] } }, "b": "#REF:$.o1.o2.a3[2]", "a": "#REF:$.o1.o2" }`; console.log('Open Chrome console to see nested fields:'); let obj = parseRefJSON(s); console.log(obj);