如何使用 C# Web 应用程序从 Oracle 数据库中检索图像
本文关键字:数据库 检索 图像 Oracle 何使用 Web 应用程序 | 更新日期: 2023-09-27 18:36:08
我想在 asp.net 中将图像从 Oracle 数据库检索到Image
控件。我试过了,但它不起作用。
这是用于将图像插入数据库的代码:
protected void btnUpload_Click(object sender, EventArgs e)
{
int imgLength = 0;
string imgContentType = null;
string imgFileName = null;
Stream imgStream = FileUpload.PostedFile.InputStream;
imgLength = FileUpload.PostedFile.ContentLength;
imgContentType = FileUpload.PostedFile.ContentType;
imgFileName = FileUpload.PostedFile.FileName;
if (imgContentType == "image/jpeg" || imgContentType == "image/gif" ||
imgContentType == "image/pjpeg"
|| imgContentType == "image/bmp")
{
OracleConnection DbConnection = new OracleConnection(con1);
DbConnection.Open();
FileStream fls;
fls = new FileStream(@imgFileName, FileMode.Open, FileAccess.Read);
byte[] blob = new byte[fls.Length];
fls.Read(blob, 0, System.Convert.ToInt32(fls.Length));
fls.Close();
string query = "insert into image(id,name,photo) values(1,'" + imgFileName + "'," + " :BlobParameter )";
// Establish a new OracleCommand
OracleCommand cmd = new OracleCommand();
cmd.CommandText = query;
cmd.Connection = DbConnection;
cmd.CommandType = CommandType.Text;
System.Data.OracleClient.OracleParameter paramImage = new System.Data.OracleClient.OracleParameter("image",
Oracle.DataAccess.Client.OracleDbType.Blob);
paramImage.ParameterName = "BlobParameter";
paramImage.Value = blob;
paramImage.Direction = ParameterDirection.Input;
cmd.Parameters.Add(paramImage);
cmd.ExecuteNonQuery();
}
桌子:
Id Name Photo
1 C:''user'pictures'animal.jpeg (BLOB)
下面是用于将图像检索到 image
控件中的代码,但此代码不起作用。在过去的两天里,我一直在为此苦苦挣扎
void GetImagesFromDatabase()
{
try
{
OracleConnection DbConnection = new OracleConnection(con1);
DbConnection.Open();
OracleCommand cmd = new OracleCommand("Select name,photo from Image", DbConnection);
OracleDataReader oda = cmd.ExecuteReader();
while (oda.Read())
{
string path = oda[0].ToString();
img.ImageUrl = path;
if(oda.GetValue(1).ToString() !=""){
FileStream fls;
fls = new FileStream(@path, FileMode.Open, FileAccess.Read);
byte[] blob = new byte[fls.Length];
fls.Read(blob, 0, System.Convert.ToInt32(fls.Length));
fls.Close();
MemoryStream memStream = new MemoryStream(blob);
img.ImageUrl = oda[2].ToString();
}
}
}
catch (Exception ex)
{
}
}
有什么想法吗?提前致谢
也许这段代码可以帮助你:
public Image byteArrayToImage(byte[] byteArrayIn)
{
MemoryStream ms = new MemoryStream(byteArrayIn);
Image returnImage = Image.FromStream(ms);
return returnImage;
}