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);

var obj={
name:'xyz',
Address:'123, Somestreet'
 }
var convertedString=JSON.stringify(obj) 
 console.log("literal object is",obj ,typeof obj);
 console.log("converted string :",convertedString);
 console.log(" convertedString type:",typeof convertedString);

我建议使用JSON。stringify，它将对象中的变量集转换为JSON字符串。

var obj = {
  name: 'myObj'
};

JSON.stringify(obj);

大多数现代浏览器都支持这种方法，但对于那些不支持的浏览器，您可以包含一个JS版本。

我需要制作一个更可配置的JSON版本。stringify，因为我必须添加注释和知道JSON路径:

const someObj = { a: { nested: { value: 'apple', }, sibling: 'peanut' }, b: { languages: ['en', 'de', 'fr'], c: { nice: 'heh' } }, c: 'butter', d: function () {} }; function* objIter(obj, indent = ' ', depth = 0, path = '') { const t = indent.repeat(depth); const t1 = indent.repeat(depth + 1); const v = v => JSON.stringify(v); yield { type: Array.isArray(obj) ? 'OPEN_ARR' : 'OPEN_OBJ', indent, depth }; const keys = Object.keys(obj); for (let i = 0, l = keys.length; i < l; i++) { const key = keys[i]; const prop = obj[key]; const nextPath = !path && key || `${path}.${key}`; if (typeof prop !== 'object') { yield { type: isNaN(key) ? 'VAL' : 'ARR_VAL', key, prop, indent, depth, path: nextPath }; } else { yield { type: 'OBJ_KEY', key, indent, depth, path: nextPath }; yield* objIter(prop, indent, depth + 1, nextPath); } } yield { type: Array.isArray(obj) ? 'CLOSE_ARR' : 'CLOSE_OBJ', indent, depth }; } const iterMap = (it, mapFn) => { const arr = []; for (const x of it) { arr.push(mapFn(x)) } return arr; } const objToStr = obj => iterMap(objIter(obj), ({ type, key, prop, indent, depth, path }) => { const t = indent.repeat(depth); const t1 = indent.repeat(depth + 1); const v = v => JSON.stringify(v); switch (type) { case 'OPEN_ARR': return '[\n'; case 'OPEN_OBJ': return '{\n'; case 'VAL': return `${t1}// ${path}\n${t1}${v(key)}: ${v(prop)},\n`; case 'ARR_VAL': return `${t1}// ${path}\n${t1}${v(prop)},\n`; case 'OBJ_KEY': return `${t1}// ${path}\n${t1}${v(key)}: `; case 'CLOSE_ARR': case 'CLOSE_OBJ': return `${t}${type === 'CLOSE_ARR' ? ']' : '}'}${depth ? ',' : ';'}\n`; default: throw new Error('Unknown type:', type); } }).join(''); const s = objToStr(someObj); console.log(s);

如果你只关心字符串、对象和数组:

function objectToString (obj) {
        var str = '';
        var i=0;
        for (var key in obj) {
            if (obj.hasOwnProperty(key)) {
                if(typeof obj[key] == 'object')
                {
                    if(obj[key] instanceof Array)
                    {
                        str+= key + ' : [ ';
                        for(var j=0;j<obj[key].length;j++)
                        {
                            if(typeof obj[key][j]=='object') {
                                str += '{' + objectToString(obj[key][j]) + (j > 0 ? ',' : '') + '}';
                            }
                            else
                            {
                                str += '\'' + obj[key][j] + '\'' + (j > 0 ? ',' : ''); //non objects would be represented as strings
                            }
                        }
                        str+= ']' + (i > 0 ? ',' : '')
                    }
                    else
                    {
                        str += key + ' : { ' + objectToString(obj[key]) + '} ' + (i > 0 ? ',' : '');
                    }
                }
                else {
                    str +=key + ':\'' + obj[key] + '\'' + (i > 0 ? ',' : '');
                }
                i++;
            }
        }
        return str;
    }

如果只是想查看用于调试的对象，可以使用

var o = {a:1, b:2} 
console.dir(o)