我怎样才能将我的JS对象转换为FormData?

我这样做的原因是,我有一个用~100个表单字段值构造的对象。

var item = {
   description: 'Some Item',
   price : '0.00',
   srate : '0.00',
   color : 'red',
   ...
   ...
}

现在我被要求将上传文件功能添加到我的表单,当然,通过JSON是不可能的,所以我计划移动到FormData。那么有什么方法可以将我的JS对象转换为FormData呢?


当前回答

我使用这个Post我的对象数据作为表单数据。

const encodeData = require('querystring');

const object = {type: 'Authorization', username: 'test', password: '123456'};

console.log(object);
console.log(encodeData.stringify(object));

其他回答

递归地

const toFormData = (f => f(f))(h => f => f(x => h(h)(f)(x)))(f => fd => pk => d => { if (d instanceof Object) { Object.keys(d).forEach(k => { const v = d[k] if (pk) k = `${pk}[${k}]` if (v instanceof Object && !(v instanceof Date) && !(v instanceof File)) { return f(fd)(k)(v) } else { fd.append(k, v) } }) } return fd })(new FormData())() let data = { name: 'John', age: 30, colors: ['red', 'green', 'blue'], children: [ { name: 'Max', age: 3 }, { name: 'Madonna', age: 10 } ] } console.log('data', data) document.getElementById("data").insertAdjacentHTML('beforeend', JSON.stringify(data)) let formData = toFormData(data) for (let key of formData.keys()) { console.log(key, formData.getAll(key).join(',')) document.getElementById("item").insertAdjacentHTML('beforeend', `<li>${key} = ${formData.getAll(key).join(',')}</li>`) } <p id="data"></p> <ul id="item"></ul>

尝试JSON。函数如下所示

var postData = JSON.stringify(item);
var formData = new FormData();
formData.append("postData",postData );

下面是一个使用Object.entries()的简单而甜蜜的解决方案,它甚至可以处理嵌套对象。

// If this is the object you want to convert to FormData...
const item = {
    description: 'First item',
    price: 13,
    photo: File
};

const formData = new FormData();

Object.entries(item).forEach(([key, value]) => {
    formData.append(key, value);
});

// At this point, you can then pass formData to your handler method

阅读更多关于Object.entries()在这里- https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Object/entries

下面是一个非常简单的TypeScript实现,基于@Vladimir Novopashin和@developer033的回答。打印稿操场

type Serializeable =
    | string
    | number
    | boolean
    | null
    | Date
    | File
    | { [x: string | number]: Serializeable }
    | Array<Serializeable>;

function serialize(
    data: Serializeable,
    parentKey = '',
    formData: FormData = new FormData()
): FormData {
    if ( typeof data === 'string') {
        formData.append(parentKey, data);
    } else if ( typeof data === 'number') {
        formData.append(parentKey, data.toString());
    } else if ( typeof data === 'boolean') {
        formData.append(parentKey, data ? 'true' : 'false');
    } else if (data === null) {
        formData.append(parentKey, 'null');
    } else if (data instanceof Date) {
        formData.append(parentKey, data.toISOString());
    } else if (data instanceof File) {
        formData.append(parentKey, data);
    } else {
        // Arrays and objects
        Object.entries(data).forEach((entry: [string | number, Serializeable]) => {
            const [key, value] = entry;
            serialize(value, parentKey ? `${parentKey}[${key}]` : key.toString(), formData);
        });
    }

    return formData;
}

使用ES6和更函数式的编程方法@adeneo的答案可能是这样的:

function getFormData(object) {
    const formData = new FormData();
    Object.keys(object).forEach(key => formData.append(key, object[key]));
    return formData;
}

或者使用.reduce()和箭头函数:

const getFormData = object => Object.keys(object).reduce((formData, key) => {
    formData.append(key, object[key]);
    return formData;
}, new FormData());