是否有一个快速和简单的方法来编码JavaScript对象到字符串,我可以通过GET请求传递?

没有jQuery,没有其他框架-只有纯JavaScript:)


当前回答

在讨论了一些最重要的答案之后,我编写了另一个实现,它也可以处理一些边缘情况

function serialize(params, prefix) {                
    return Object.entries(params).reduce((acc, [key, value]) => {
        // remove whitespace from both sides of the key before encoding
        key = encodeURIComponent(key.trim());

        if (params.constructor === Array ) {
          key = `${prefix}[]`;
        } else if (params.constructor === Object) {
          key = (prefix ? `${prefix}[${key}]` : key);
        }

        /**
         *  - undefined and NaN values will be skipped automatically
         *  - value will be empty string for functions and null
         *  - nested arrays will be flattened
         */
        if (value === null || typeof value === 'function') {
            acc.push(`${key}=`);
        } else if (typeof value === 'object') {
            acc = acc.concat(serialize(value, key));
        } else if(['number', 'boolean', 'string'].includes(typeof value) && value === value) { // self-check to avoid NaN
            acc.push(`${key}=${encodeURIComponent(value)}`);
        }

        return acc;
    }, []);
}

function objectToQueryString(queryParameters) {
    return queryParameters ? serialize(queryParameters).join('&'): '';
}

let x = objectToQueryString({
    foo: 'hello world',
    bar: {
      blah: 123,
      list: [1, 2, 3],
        'nested array': [[4,5],[6,7]] // will be flattened
    },
    page: 1,
    limit: undefined, // field will be ignored
    check: false,
    max: NaN, // field will be ignored
    prop: null,
    ' key value': 'with spaces' // space in key will be trimmed out
});
  
console.log(x); // foo=hello%20world&bar[blah]=123&bar[list][]=1&bar[list][]=2&bar[list][]=3&bar[nested%20array][][]=4&bar[nested%20array][][]=5&bar[nested%20array][][]=6&bar[nested%20array][][]=7&page=1&check=false&prop=&key%20value=with%20spaces

其他回答

我的实现编码一个对象作为一个查询字符串,使用减少:

export const encodeAsQueryString = (params) => (
  Object.keys(params).reduce((acc, key)=>(
    params.hasOwnProperty(key) ? (
      [...acc, encodeURIComponent(key) + '=' + encodeURIComponent(params[key])]
    ) : acc
  ), []).join('&')
);

如果有很多嵌套对象,前面的答案就不起作用了。

相反,你可以从jquery-param/jquery-param.js中选择函数参数。这对我来说非常有效!

    var param = function (a) {
    var s = [], rbracket = /\[\]$/,
        isArray = function (obj) {
            return Object.prototype.toString.call(obj) === '[object Array]';
        }, add = function (k, v) {
            v = typeof v === 'function' ? v() : v === null ? '' : v === undefined ? '' : v;
            s[s.length] = encodeURIComponent(k) + '=' + encodeURIComponent(v);
        }, buildParams = function (prefix, obj) {
            var i, len, key;

            if (prefix) {
                if (isArray(obj)) {
                    for (i = 0, len = obj.length; i < len; i++) {
                        if (rbracket.test(prefix)) {
                            add(prefix, obj[i]);
                        } else {
                            buildParams(prefix + '[' + (typeof obj[i] === 'object' ? i : '') + ']', obj[i]);
                        }
                    }
                } else if (obj && String(obj) === '[object Object]') {
                    for (key in obj) {
                        buildParams(prefix + '[' + key + ']', obj[key]);
                    }
                } else {
                    add(prefix, obj);
                }
            } else if (isArray(obj)) {
                for (i = 0, len = obj.length; i < len; i++) {
                    add(obj[i].name, obj[i].value);
                }
            } else {
                for (key in obj) {
                    buildParams(key, obj[key]);
                }
            }
            return s;
        };

    return buildParams('', a).join('&').replace(/%20/g, '+');
};

下面是Object.entries的简洁递归版本。它处理任意嵌套的数组,但不处理嵌套的对象。它还会删除空元素:

const format = (k,v) => v !== null ? `${k}=${encodeURIComponent(v)}` : ''

const to_qs = (obj) => {
    return [].concat(...Object.entries(obj)
                       .map(([k,v]) => Array.isArray(v) 
                          ? v.map(arr => to_qs({[k]:arr})) 
                          : format(k,v)))
           .filter(x => x)
           .join('&');
}

例如:

let json = { 
    a: [1, 2, 3],
    b: [],              // omit b
    c: 1,
    d: "test&encoding", // uriencode
    e: [[4,5],[6,7]],   // flatten this
    f: null,            // omit nulls
    g: 0
};

let qs = to_qs(json)

=> "a=1&a=2&a=3&c=1&d=test%26encoding&e=4&e=5&e=6&e=7&g=0"

这是对已接受的解的补充。这适用于对象和对象数组:

parseJsonAsQueryString = function (obj, prefix, objName) {
    var str = [];
    for (var p in obj) {
        if (obj.hasOwnProperty(p)) {
            var v = obj[p];
            if (typeof v == "object") {
                var k = (objName ? objName + '.' : '') + (prefix ? prefix + "[" + p + "]" : p);
                str.push(parseJsonAsQueryString(v, k));
            } else {
                var k = (objName ? objName + '.' : '') + (prefix ? prefix + '.' + p : p);
                str.push(encodeURIComponent(k) + "=" + encodeURIComponent(v));
                //str.push(k + "=" + v);
            }
        }
    }
    return str.join("&");
}

我还添加了objName,如果你使用对象参数,像在ASP。NET MVC动作方法。

单行转换对象为查询字符串,以防有人再次需要它:

let Objs = { a: 'obejct-a', b: 'object-b' }

Object.keys(objs).map(key => key + '=' + objs[key]).join('&')

// The result will be a=object-a&b=object-b