javascript - 带字幕的多图像文件上传

Question

我设法通过 foreach 循环获取了字幕，但现在我遇到了一个新问题。

由于嵌套循环，我在数据库中得到了重复项，请检查下面的代码。

JavaScript

window.onload = function () {
    if (window.File && window.FileList && window.FileReader) {
        var filesInput = document.getElementById("galleryFilesAdd");
        filesInput.addEventListener("change", function (event) {
            var files = event.target.files; //FileList object
            var output = document.getElementById("result");
            for (var i = 0; i < files.length; i++) {
                var file = files[i];
                if (!file.type.match('image'))
                    continue;
                var picReader = new FileReader();
                picReader.addEventListener("load", function (event) {
                    var picFile = event.target;
                    var div = document.createElement("div");
                    div.innerHTML = "<img class='thumbnail img-responsive' alt='" + picFile.name + "' + height='220' width='300'; src='" + picFile.result + "'" +
                            "title='" + picFile.name + "'/><button type='button' class='delete btn btn-default' class='remove_pic'> <span class='glyphicon glyphicon-remove' aria-hidden='true'></span></button><input type='text' id ='imagecaption[]' name='imagecaption[]' class='form-control' placeholder='Add Image Caption'>"
                    output.insertBefore(div, null);
                    div.children[1].addEventListener("click", function (event) {
                        div.parentNode.removeChild(div);
                    });
                });
                //Read the image
                picReader.readAsDataURL(file);
            }
        });
    }
    else {
        console.log("Your browser does not support File API");
    }
}

Controller

public async Task<ActionResult> AddHotel(HotelViewModels.AddHotel viewModel, IEnumerable<HttpPostedFileBase> galleryFilesAdd)
{
    try
    {
        if (ModelState.IsValid)
        {

            foreach (var files in galleryFilesAdd)
            {
                var fileName = Guid.NewGuid().ToString("N");
                var extension = Path.GetExtension(files.FileName).ToLower();
                string thumbpath, imagepath = "";
                using (var img = Image.FromStream(files.InputStream))
                {
                  foreach (var caption in viewModel.imagecaption)
                  {
                    var galleryImg = new hotel_gallery_image
                    {
                        hotel_id = hotel.id,
                        thumbPath = String.Format("/Resources/Images/Hotel/GalleryThumb/{0}{1}", fileName, extension),
                        imagePath = String.Format("/Resources/Images/Hotel/Gallery/{0}{1}", fileName, extension),
                        entry_datetime = DateTime.Now,
                        guid = Guid.NewGuid().ToString("N"),
                        enabled = true,
                        image_caption = caption
                    };
                    db.hotel_gallery_image.Add(galleryImg);
                }
            }
          }

            await db.SaveChangesAsync();
            return RedirectToAction("Index", "Hotel");
        }
    }
    catch (DbEntityValidationException ex)
    {
        string errorMessages = string.Join("; ", ex.EntityValidationErrors.SelectMany(x => x.ValidationErrors).Select(x => x.PropertyName + ": " + x.ErrorMessage));
        throw new DbEntityValidationException(errorMessages);
    }
    viewModel.Country = await db.countries.ToListAsync();
    return View(viewModel);
}

和 View 模型

public string[] imagecaption { get; set; }

向数据库中插入数据

Answer 1

我觉得是你的问题

image_caption = viewModel.imagecaption

因为您遍历 galleryFilesAdd 中的 var 文件，所以您在每次迭代中都使用 viewModel 中对相同 image_caption 的引用，因此您需要根据其他数据(文件名或您 viewmodel 包含的其他数据)过滤您的 image_caption。

更新理想情况下，如果您在 ViewModel 和文件(例如文件名)中具有相同的属性，那么您可以执行类似 thatimage_caption = viewModel.FirstOrDefault(x=>x.Filename == filename).imagecaption

为了更具体，如果您为您的 Viemodel 和 galleryFilesAdd 类提供代码会有所帮助。

更新 2

在你的例子中，第二次 foreach 你遍历 imagecaption 数组的whole 集合，每次迭代通过 galleryFilesAdd 集合，这会导致双数据你数据库。如果您可以为第一个文件顺序获取字幕，则从 imagecaption 数组中获取第一个元素，依此类推，那么您可以使用如下代码:

if (ModelState.IsValid)
        {
            int index = 0;
            foreach (var files in galleryFilesAdd)
            {
                var fileName = Guid.NewGuid().ToString("N");
                var extension = Path.GetExtension(files.FileName).ToLower();
                string thumbpath, imagepath = "";
                using (var img = Image.FromStream(files.InputStream))
                {
                 if(index < viewModel.imagecaption.Length){
                    var galleryImg = new hotel_gallery_image
                    {
                        hotel_id = hotel.id,
                        thumbPath = String.Format("/Resources/Images/Hotel/GalleryThumb/{0}{1}", fileName, extension),
                        imagePath = String.Format("/Resources/Images/Hotel/Gallery/{0}{1}", fileName, extension),
                        entry_datetime = DateTime.Now,
                        guid = Guid.NewGuid().ToString("N"),
                        enabled = true,
                        image_caption = viewModel.imagecaption[index]
                    };
                    db.hotel_gallery_image.Add(galleryImg);
                    index++;
                   }
            }
          }