如何使用 MVC 4 将图像保存到数据库 [英] How to save an image to Database using MVC 4

问题描述

所以我有一个购物车项目，我必须将图像保存到数据库而不是上传到服务器，这是我的模型

命名空间 ShoppingCart.Models{[绑定(排除 =ItemID")]公共类项目{[ScaffoldColumn(false)]公共 int ItemID { 获取；放;}[显示名称(类别")]公共 int 类别 ID { 获取；放;}[显示名称(品牌")]公共 int BrandID { 获取；放;}[必填(ErrorMessage = "需要一个名字")][字符串长度(160)]公共字符串标题{获取；放;}公共字符串 描述 { 获取；放;}[必填(ErrorMessage =需要价格")][范围(0.01, 100.00,ErrorMessage = "价格必须在 0.01 和 500.00 之间")]公共十进制价格{得到；放;}[DisplayName("专辑封面网址")][字符串长度(1024)]公共字符串 ItemArtUrl { 获取；放;}公共字节[]图片{获取；放;}公共虚拟类别类别{获取；放;}公共虚拟品牌品牌{得到;放;}公共虚拟列表订单详情 { 获取；放;}}}

所以我不确定如何使用控制器插入图像或视图来显示它们，我搜索了有关此的信息，但我真的找不到任何东西，我首先使用实体​​框架代码.

解决方案

有两种简单的方法来处理图像——一种是简单地在控制器中返回图像本身:

 [HttpGet][允许匿名]公共 ActionResult ViewImage(int id){var item = _shoppingCartRepository.GetItem(id);byte[] buffer = item.Picture;return File(buffer, "image/jpg", string.Format("{0}.jpg", id));}

视图只会引用它:

此外，您可以将其包含在 ViewModel 中:

 viewModel.ImageToShow = Convert.ToBase64String(item.Picture);

并在视图中:

 @Html.Raw("<img src="data:image/jpeg;base64," + viewModel.ImageToShow + ""/>");

对于数据存储，您只需使用字节数组 (varbinary(max)) 或 blob 或任何兼容类型.

上传图片

这里，一个名为 HeaderImage 的对象是一个 EntityFramework EntityObject.控制器看起来像:

 [HttpPost]公共 ActionResult UploadImages(HttpPostedFileBase[] uploadImages){如果 (uploadImages.Count() <= 1){return RedirectToAction("BrowseImages");}foreach(uploadImages 中的 var 图像){如果 (image.ContentLength > 0){byte[] imageData = null;使用 (var binaryReader = new BinaryReader(image.InputStream)){imageData = binaryReader.ReadBytes(image.ContentLength);}var headerImage = 新的 HeaderImage{图像数据 = 图像数据，ImageName = image.FileName,IsActive = 真};imageRepository.AddHeaderImage(headerImage);}}return RedirectToAction("BrowseImages");}

视图看起来像:

 @using (Html.BeginForm("UploadImages", "Home", FormMethod.Post, new { enctype = "multipart/form-data" })){<div class="row"><span class="span4"><input type="file" name="uploadImages" multiple="multiple" class="input-files"/></span><span class="span2"><input type="submit" name="button" value="Upload" class="btn btn-upload"/></span>

}

So I have a project which is a Shopping Cart, I have to save images to the database instead of uploading them to the server, here is my model

namespace ShoppingCart.Models
{
    [Bind(Exclude = "ItemID")]
    public class Item
    {
        [ScaffoldColumn(false)]
        public int ItemID { get; set; }
        [DisplayName("Category")]
        public int CategoryID { get; set; }
        [DisplayName("Brand")]
        public int BrandID { get; set; }
        [Required(ErrorMessage = "A Name is required")]
        [StringLength(160)]
        public string Title { get; set; }
        public string Description { get; set; }
        [Required(ErrorMessage = "Price is required")]
        [Range(0.01, 100.00,
            ErrorMessage = "Price must be between 0.01 and 500.00")]
        public decimal Price { get; set; }
        [DisplayName("Album Art URL")]
        [StringLength(1024)]

        public string ItemArtUrl { get; set; }
        public byte[] Picture { get; set; }

        public virtual Category Category { get; set; }
        public virtual Brand Brand { get; set; }
        public virtual List<OrderDetail> OrderDetails { get; set; }
    }
}

So Im unsure how to go about the controller to insert images or the view to display them, I have search for information about this but I cant really find anything, Im using entity framework code first.

解决方案

There are two easy ways to do images -- one is to simply return the image itself in the controller:

    [HttpGet]
    [AllowAnonymous]
    public ActionResult ViewImage(int id)
    {
        var item = _shoppingCartRepository.GetItem(id);
        byte[] buffer = item.Picture;
        return File(buffer, "image/jpg", string.Format("{0}.jpg", id));
    }

And the view would just reference it:

    <img src="Home/ViewImage/10" />

Additionally, you can include it in the ViewModel:

    viewModel.ImageToShow = Convert.ToBase64String(item.Picture);

and in the view:

    @Html.Raw("<img src="data:image/jpeg;base64," + viewModel.ImageToShow + "" />");

For the data-store, you would simply use a byte array (varbinary(max)) or blob or any compatible type.

Uploading images

Here, an object called HeaderImage is an EntityFramework EntityObject. The controller would look something like:

    [HttpPost]
    public ActionResult UploadImages(HttpPostedFileBase[] uploadImages)
    {
        if (uploadImages.Count() <= 1)
        {
            return RedirectToAction("BrowseImages");
        }

        foreach (var image in uploadImages)
        {
            if (image.ContentLength > 0)
            {
                byte[] imageData = null;
                using (var binaryReader = new BinaryReader(image.InputStream))
                {
                    imageData = binaryReader.ReadBytes(image.ContentLength);
                }
                var headerImage = new HeaderImage
                {
                    ImageData = imageData,
                    ImageName = image.FileName,
                    IsActive = true
                };
                imageRepository.AddHeaderImage(headerImage);
            }
        }
        return RedirectToAction("BrowseImages");
    }

The View would look something like:

            @using (Html.BeginForm("UploadImages", "Home", FormMethod.Post, new { enctype = "multipart/form-data" }))
            {
                <div class="row">
                    <span class="span4">
                        <input type="file" name="uploadImages" multiple="multiple" class="input-files"/>
                    </span>
                    <span class="span2">
                        <input type="submit" name="button" value="Upload" class="btn btn-upload" />
                    </span>
                </div>
            }

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