我正在博客网站上工作。用户可以浏览'通过FileUpload控件并选择要与其帖子一起上传的多个图像。每个帖子在数据库中都有唯一的消息ID。我已经想出如何在一个消息ID下将所有上传的文件插入到数据库中,如下所示:(我将它们作为数据类型插入'图像')
try
{
conn.Open();
SqlCommand cmdInsert = new SqlCommand("INSERT INTO BlogMessages (Title, Message, Date, Author, IPAddress) VALUES (@Title, @Message, @Date, @Author, @IPAddress)", conn);
cmdInsert.Parameters.AddWithValue("@Title", tbTitle.Text.Trim());
cmdInsert.Parameters.AddWithValue("@Message", tbMessage.Text.Trim());
cmdInsert.Parameters.AddWithValue("@Date", DateTime.Now);
cmdInsert.Parameters.AddWithValue("@Author", tbAuthor.Text.Trim());
cmdInsert.Parameters.AddWithValue("@IPAddress", ip);
cmdInsert.ExecuteNonQuery();
if (imageUpload.HasFiles)
{
System.Text.StringBuilder sb = new System.Text.StringBuilder();
HttpPostedFile file;
SqlCommand maxMessId = new SqlCommand("SELECT Max(MessageID) FROM BlogMessages", conn);
lastMessageID = Convert.ToInt32(maxMessId.ExecuteScalar());
foreach (var uploadedFile in imageUpload.PostedFiles)
{
file = uploadedFile;
MemoryStream ms = new MemoryStream();
file.InputStream.CopyTo(ms);
byte[] byts = ms.ToArray();
ms.Dispose();
SqlCommand cmdInsertImage = new SqlCommand("INSERT INTO BlogImages(Image, MessageID) VALUES (@Image, @MessageID)", conn);
cmdInsertImage.Parameters.AddWithValue("@Image", SqlDbType.Image).Value = byts;
cmdInsertImage.Parameters.AddWithValue("@MessageID", lastMessageID);
cmdInsertImage.ExecuteNonQuery();
byts = null;
cmdInsertImage = null;
}
}
但是,我无法动态检索图像以便在我的ImageHandler中显示。似乎我能够将所有图像都放在特定的MessageID下并将它们插入到数据集中,但之后我正在寻找指导,而我无法通过研究找到一个可行的解决方案迄今。以下是ImageHandler.ashx.cs的public void Process Request中的相关代码:
try
{
int messageid = Convert.ToInt32(context.Request.QueryString["mid"]);
SqlDataAdapter sda = new SqlDataAdapter("SELECT Image from BlogImages WHERE Image IS NOT NULL AND MessageID=" + messageid, conn);
System.Data.DataSet data = new DataSet();
sda.Fill(data);
if (data !=null)
{
byte[] result = (byte[])data.Tables[0].Rows[0]["ImageContent"];
result.Initialize();
context.Response.ContentType = data.Tables[0].Rows[0]["ImageExt"].ToString();
context.Response.BinaryWrite(result);
}
else
{
context.Response.WriteFile("No Image");
}
}
谢谢!