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
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;
}
其他回答
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());
我有一个场景，在构造表单数据时，嵌套的JSON必须以线性方式序列化，因为这是服务器期望值的方式。所以，我写了一个小的递归函数来翻译JSON，就像这样:
{
"orderPrice":"11",
"cardNumber":"************1234",
"id":"8796191359018",
"accountHolderName":"Raj Pawan",
"expiryMonth":"02",
"expiryYear":"2019",
"issueNumber":null,
"billingAddress":{
"city":"Wonderland",
"code":"8796682911767",
"firstname":"Raj Pawan",
"lastname":"Gumdal",
"line1":"Addr Line 1",
"line2":null,
"state":"US-AS",
"region":{
"isocode":"US-AS"
},
"zip":"76767-6776"
}
}
变成这样:
{
"orderPrice":"11",
"cardNumber":"************1234",
"id":"8796191359018",
"accountHolderName":"Raj Pawan",
"expiryMonth":"02",
"expiryYear":"2019",
"issueNumber":null,
"billingAddress.city":"Wonderland",
"billingAddress.code":"8796682911767",
"billingAddress.firstname":"Raj Pawan",
"billingAddress.lastname":"Gumdal",
"billingAddress.line1":"Addr Line 1",
"billingAddress.line2":null,
"billingAddress.state":"US-AS",
"billingAddress.region.isocode":"US-AS",
"billingAddress.zip":"76767-6776"
}
服务器将接受这种转换格式的表单数据。
函数如下:
function jsonToFormData (inJSON, inTestJSON, inFormData, parentKey) {
// http://stackoverflow.com/a/22783314/260665
// Raj: Converts any nested JSON to formData.
var form_data = inFormData || new FormData();
var testJSON = inTestJSON || {};
for ( var key in inJSON ) {
// 1. If it is a recursion, then key has to be constructed like "parent.child" where parent JSON contains a child JSON
// 2. Perform append data only if the value for key is not a JSON, recurse otherwise!
var constructedKey = key;
if (parentKey) {
constructedKey = parentKey + "." + key;
}
var value = inJSON[key];
if (value && value.constructor === {}.constructor) {
// This is a JSON, we now need to recurse!
jsonToFormData (value, testJSON, form_data, constructedKey);
} else {
form_data.append(constructedKey, inJSON[key]);
testJSON[constructedKey] = inJSON[key];
}
}
return form_data;
}
调用:
var testJSON = {};
var form_data = jsonToFormData (jsonForPost, testJSON);
我使用testJSON只是为了查看转换后的结果，因为我无法提取form_data的内容。AJAX post call:
$.ajax({
type: "POST",
url: somePostURL,
data: form_data,
processData : false,
contentType : false,
success: function (data) {
},
error: function (e) {
}
});
使用jquery，你可以通过$.param(obj)简单地做到这一点。
例子: Const obj = { 描述:'Some Item'， 价格:0.00, srate:“0.00”, 颜色:红色的 ｝ Const form_obj = $.param(obj); . ajax({美元 url:“example.com”, 方法:“文章”, 数据:form_obj }) < script src = " https://cdnjs.cloudflare.com/ajax/libs/jquery/3.3.1/jquery.min.js " > < /脚本>
我参考了古德拉丹的回答。我用Typescript格式编辑了一下。
class UtilityService {
private appendFormData(formData, data, rootName) {
let root = rootName || '';
if (data instanceof File) {
formData.append(root, data);
} else if (Array.isArray(data)) {
for (var i = 0; i < data.length; i++) {
this.appendFormData(formData, data[i], root + '[' + i + ']');
}
} else if (typeof data === 'object' && data) {
for (var key in data) {
if (data.hasOwnProperty(key)) {
if (root === '') {
this.appendFormData(formData, data[key], key);
} else {
this.appendFormData(formData, data[key], root + '.' + key);
}
}
}
} else {
if (data !== null && typeof data !== 'undefined') {
formData.append(root, data);
}
}
}
getFormDataFromObj(data) {
var formData = new FormData();
this.appendFormData(formData, data, '');
return formData;
}
}
export let UtilityMan = new UtilityService();
很简单，可以这样做:
var item: { some1: "ajbd" , some2: "dds".. }
let myFormData = new FormData();
const abc = item.some1;
const xyz = item.some2;
myFormData.append('field1', abc);
myFormData.append('field2', xyz);
fetch('http:url', {
method: 'POST',
headers: {
'Content-Type': false,
},
body: myFormData,
}).
do promise ..
