参数转换

1. 对象转 form-data 参数

paramsToFormData(obj) {
    const formData = new FormData();
    Object.keys(obj).forEach((key) => {
        if (obj[key] instanceof Object) {
            formData.append(key, obj[key]);
            return;
        } else {
            formData.append(key, obj[key]);
        }
    });
    return formData;
},