Question

我正在尝试将Oracle Long Raw类型转换为c＃中的byte []。当我得到byte []时，我需要创建一个图像并保存在我的内容的某个文件夹中，之后我需要返回我的视图的路径，并从visjs库中为节点提供在画布中显示我的图像的路径。

问题是，当我尝试使用memorystream生成我的图像时，我得到“参数无效”错误。我尝试了一些替代方案，但都失败了。

首先：我尝试了这个解决方案：https://stackoverflow.com/a/3801289/5692322但是我遇到了同样的错误。

然后，我尝试了这个：https://stackoverflow.com/a/16576471/5692322我得到了相同的错误。

所以..我尝试在我的javascript上渲染我的图像，但仍然无效。当我尝试使用View时，我得到了一张空白图片。

这是我目前的代码：

{
            PropertyInfo propertyToEvaluate = property;

            for (int i = 0; i <= dr.FieldCount - 1; i++)
            {
                if (nomePropriedade.Equals(dr.GetName(i).ToLower()))
                {
                    object valor = null;

                    if (!object.ReferenceEquals(valor, DBNull.Value))
                    {
                        if (!String.IsNullOrEmpty(dr.GetValue(i).ToString()))
                        {
                            if (object.ReferenceEquals(propertyToEvaluate.PropertyType, typeof(int)) ||
                                object.ReferenceEquals(propertyToEvaluate.PropertyType, typeof(int?)))
                            {
                                valor = Convert.ToInt32(dr.GetValue(i));
                            }
                            else if (object.ReferenceEquals(propertyToEvaluate.PropertyType, typeof(short)) ||
                                     object.ReferenceEquals(propertyToEvaluate.PropertyType, typeof(short?)))
                            {
                                valor = short.Parse(dr.GetValue(i).ToString());
                            }
                            else if (object.ReferenceEquals(propertyToEvaluate.PropertyType, typeof(long)) ||
                                     object.ReferenceEquals(propertyToEvaluate.PropertyType, typeof(long?)))
                            {
                                valor = Convert.ToInt64(dr.GetValue(i));
                            }
                            else if (object.ReferenceEquals(propertyToEvaluate.PropertyType, typeof(decimal)) ||
                                     object.ReferenceEquals(propertyToEvaluate.PropertyType, typeof(decimal?)))
                            {
                                valor = Convert.ToDecimal(dr.GetValue(i));
                            }
                            else if (object.ReferenceEquals(propertyToEvaluate.PropertyType, typeof(double)) ||
                                     object.ReferenceEquals(propertyToEvaluate.PropertyType, typeof(double?)))
                            {
                                valor = Convert.ToDouble(dr.GetValue(i));
                            }
                            else if (object.ReferenceEquals(propertyToEvaluate.PropertyType, typeof(float)) ||
                                     object.ReferenceEquals(propertyToEvaluate.PropertyType, typeof(float?)))
                            {
                                valor = float.Parse(dr.GetValue(i).ToString());
                            }
                            else if (object.ReferenceEquals(propertyToEvaluate.PropertyType, typeof(byte)) ||
                                 object.ReferenceEquals(propertyToEvaluate.PropertyType, typeof(byte?)))
                            {
                                valor = byte.Parse(dr.GetValue(i).ToString());
                            }
                            else if (object.ReferenceEquals(propertyToEvaluate.PropertyType, typeof(byte[])) ||
                             object.ReferenceEquals(propertyToEvaluate.PropertyType, typeof(byte[])))
                            {
                                //Get Long Raw and conver to byte[]
                                valor = Encoding.ASCII.GetBytes(dr.GetValue(i).ToString());
                            }
                            else if (object.ReferenceEquals(propertyToEvaluate.PropertyType, typeof(bool)))
                            {
                                valor = (dr.GetValue(i).Equals("0")) ? false : true; //Convert.ToBoolean(dr.GetValue(i));
                            }
                            else if (object.ReferenceEquals(propertyToEvaluate.PropertyType, typeof(DateTime)) || object.ReferenceEquals(propertyToEvaluate.PropertyType, typeof(DateTime?)))
                            {
                                valor = Convert.ToDateTime(dr.GetValue(i));
                            }
                            else if (propertyToEvaluate.PropertyType.IsEnum)
                            {
                                Type enumType = propertyToEvaluate.PropertyType;

                                valor = EnumExtensao.Converter(enumType, dr.GetValue(i).ToString().Trim());
                            }
                            else
                            {
                                valor = dr.GetValue(i).ToString().Trim();
                            }
                            if ((!object.ReferenceEquals(dr.GetValue(i), DBNull.Value)))
                            {
                                propertyToEvaluate.SetValue(item, valor, null);
                            }

                            break;
                        }
                    }
                }
            }
        }

Controller.cs

//Convert byte[] to base64
string imagemStr = Convert.ToBase64String(obterPremissas[i].nom_ident_denho);

//Save image in path and return to View
//This approach it's returning  all images with same size and blank                   
var path = SaveImage(imagemStr, "Foo");


       public static string SaveImage(string ImgStr, string imgName)
        {
            String path = System.Web.HttpContext.Current.Server.MapPath("~/Content/Imagens/ImageStorage");
            //Check if directory exist
            if (!System.IO.Directory.Exists(path))
            {
                System.IO.Directory.CreateDirectory(path); //Create directory if it doesn't exist
            }

            string imageName = imgName + ".jpg";

            //set the image path
            string imgPath = Path.Combine(path, imageName);

            byte[] imageBytes = Convert.FromBase64String(ImgStr);
            Image x = (Bitmap)((new ImageConverter()).ConvertFrom(imageBytes));

            System.IO.File.WriteAllBytes(imgPath, imageBytes);

            path = path + "\\" + imageName;

            return path;
        }

正如评论所说，我在这种方法上得到了空白图像，由于这张空白图像，现在我正在尝试这个：

Bitmap newBitmap = GetImageFromByteArray(obterPremissas[i].nom_ident_denho);

public static Bitmap GetImageFromByteArray(byte[] byteArray)
        {
            Bitmap bm = (Bitmap)_imageConverter.ConvertFrom(byteArray);

            if (bm != null && (bm.HorizontalResolution != (int)bm.HorizontalResolution ||
                               bm.VerticalResolution != (int)bm.VerticalResolution))
            {
                bm.SetResolution((int)(bm.HorizontalResolution + 0.5f),
                                 (int)(bm.VerticalResolution + 0.5f));
            }

            return bm;
        }

但在第一行Bitmap bm = (Bitmap)_imageConverter.ConvertFrom(byteArray);

当我使用memoryStream“参数无效”时，我收到同样的错误。任何人都知道如何在C＃中处理Oracle Long Raw？

参数无效：将Oracle Long Raw转换为byte []

0 个答案: