dongya2029 2018-10-18 22:47
浏览 156


I'm trying to access an array on a multipart-form-data request.

On my js code I add to the formData the object that I need this way:

for (const key in property) {
    if (typeof property[key] !== 'undefined') {
        console.log(key, property[key]);
        formData.append(`property[${key}]`, property[key]);

The property has the array images and the value is an array like this:

enter image description here

Also in the same forData I send all the data from the images that I want to handle, and in this case the property contains an array of objects that are images previously stored in the database. So, in my controller I have to following

 // Images that are already in database
 $propertyData = $request->input('property');
 $images = isset($propertyData['images'])? $propertyData['images'] : []
 foreach($images as $i) {
    $image = Image::find((int)$i['id']);
    if ( !is_null($image) ) {

But I got the error: Invalid argument supplied for foreach()

I've tried to even convert each image on the javascript code to an array like the property, but i got the same error.

  • 写回答

1条回答 默认 最新

  • dongpu1881 2018-10-18 23:19

    You cannot directly append objects or arrays to FormData. You must add the keys and values one by one.

    A way to do that is like so:

    var formData = new FormData;
    var arr = ['this', 'is', 'an', 'array'];
    for (var i = 0; i < arr.length; i++) {
        formData.append('arr[]', arr[i]);

    I use a helper function (note that this is in ES6 syntax) to do this:

    export function appendFormdata(formData, data, previousKey) {
        if (data instanceof Object) {
            Object.keys(data).forEach(key => {
                const value = data[key];
                if (previousKey) {
                    key = `${previousKey}[${key}]`;
                if (value instanceof Object && !Array.isArray(value) && !(value instanceof File)) {
                    return appendFormdata(formData, value, key);
                if (Array.isArray(value)) {
                    value.forEach((val, i) => {
                        return appendFormdata(formData, val, `${key}[${i}]`);
                } else {
                    formData.append(key, value);

    For more details refer: appending array to FormData and send via AJAX and Convert JS Object to form data

    本回答被题主选为最佳回答 , 对您是否有帮助呢?



  • ¥45 工程软件单片机设计课题要求
  • ¥15 在centos7安装conda
  • ¥15 c#调用yolo3 dll文件获取的数据对不上
  • ¥20 WPF 如何实现多语言,label 和cs(live Charts)中是否都能翻译
  • ¥15 STM32F103上电短路问题
  • ¥15 关于#单片机#的问题:以ATMEGA128或相近型号单片机为控制器设计直流电机调速的闭环控制系统(相关搜索:设计报告|软件设计|流程图)
  • ¥15 打开软件提示错误:failed to get wglChoosePixelFormatARB
  • ¥15 (标签-python|关键词-char)
  • ¥15 python+selenium,在新增时弹出了一个输入框
  • ¥15 苹果验机结果的api接口哪里有??单次调用1毛钱及以下。