Thank you for the link. This one seems better than I used.
After reading the ole object from db, I saved it to C: as file1.bmp and
displayed on the web. But it can not be displayed. After I manually sent the
file to wordpad, it shows
System.Byte [ ]
Now I suspect my saving an image might be wrong. The table has 2 columns:
username and userfile. Userfile column shows
..ong binary data
I can not find a way to verify if data was saved ok? But saving does not
report any errors. I am attached my saving and reading codes here to see if
anyone can help?
Thanks. -dale
private void btnSaveToDB_Click(object sender, System.EventArgs e)
{
if (dListUsers.SelectedValue == "")
{
lblFileAccess.Text = "You need to select an user first!";
return;
}
curFileName = myFile.PostedFile.FileName;
// only the attched file name not its path
string c = System.IO.Path.GetFileName(curFileName);
// Read a bitmap contents in a stream
FileStream fs = new FileStream(curFileName, FileMode.OpenOrCreate,
FileAccess.Read);
byte[] rawData = new byte[fs.Length];
fs.Read(rawData, 0, System.Convert.ToInt32(fs.Length));
fs.Close();
// Construct a SQL string and a connection object
OleDbConnection dbConn;
OleDbCommand dbCmd;
string applicationState = ((string)(Application["DBType"])).ToLower();
string sConn = dbClass.Connect(applicationState);
string sSQL;
sSQL = ("INSERT INTO UserFiles (UserName,UserFile) "
+ ("VALUES ("
+ (dbClass.DelimString(dListUsers.SelectedValue) + (","
+ ("\'"+rawData + "\')")))));
try
{
// write the visit log entry
dbConn = new OleDbConnection(sConn);
dbConn.Open();
dbCmd = new OleDbCommand(sSQL, dbConn);
dbCmd.ExecuteNonQuery();
dbConn.Close();
lblFileAccess.Text = "The file has been saved successfully for "
+ dListUsers.SelectedValue + ".";
return;
}
catch (Exception excep)
{
Debug.WriteLine(excep.Message);
lblFileAccess.Text = "The file has not been saved successfully for "
+ dListUsers.SelectedValue + ".";
return;
}
}
private void btnReadFmDB_Click(object sender, System.EventArgs e)
{
OleDbConnection dbConn;
OleDbCommand dbCmd;
OleDbDataReader dbDR;
string applicationState = ((string)(Application["DBType"])).ToLower();
string sConn = dbClass.Connect(applicationState);
// Construct a SQL string and a connection object
string sql = "SELECT UserFile FROM UserFiles WHERE Username =\'"
+ dListUsers.SelectedValue + "\'";
FileStream fs;
BinaryWriter bw;
int bufferSize = 300000;
//byte[] outbyte;
byte[] outbyte = new byte[300000 - 1];
long retval;
//long startIndex = 0;
//string pub_id = "";
try
{
dbConn = new OleDbConnection(sConn);
dbConn.Open();
dbCmd = new OleDbCommand(sql, dbConn);
dbDR = dbCmd.ExecuteReader(CommandBehavior.CloseConnectio n);
while (dbDR.Read())
{
fs = new FileStream(savedImageName, FileMode.OpenOrCreate,
FileAccess.Write);
bw = new BinaryWriter(fs);
//startIndex = 0;
retval = dbDR.GetBytes(0, 0, outbyte, 0, bufferSize);
bw.Write(outbyte);
bw.Flush();
// Close the output file.
bw.Close();
fs.Close();
}
// get the end
dbConn.Close();
}
catch (Exception excep)
{
Debug.WriteLine(excep.Message);
return;
}
// Display image
//curImage = System.Web.UI.WebControls.Image.FromFile(savedImag eName);
imgBox.ImageUrl = savedImageName;
}
"Ollie Riches" wrote:
[color=blue]
> have you tried using any of the free converters:
>
>
http://www.developerfusion.co.uk/uti...btocsharp.aspx
>
> HTH
>
> Ollie Riches
>
> "dale zhang" <dalezhang@discussions.microsoft.com> wrote in message
> news:07D45D31-818B-4EC0-AC48-AB0964C67A5E@microsoft.com...[color=green]
> > Hi,
> >
> > I am trying to read an image from MS Access DB based on the following
> > article:
> >
> >
http://www.vbdotnetheaven.com/Code/Sept2003/2175.asp
> >
> > The article author is using PictureBox for windows application, while I am
> > doing for web. I can only find Image from web forms control and HTML
> > control.
> > This may be the root cause of my problem. For read button, I converted his
> > VB
> > to the C#. But the compiler complains:
> >
> > 1. For Image,
> > C:\Inetpub\wwwroot\passwordProtectCSharp\adminUser File.aspx.cs(421):
> > 'Image'
> > is an ambiguous reference
> >
> > 2. For imgBox.Image,
> > C:\Inetpub\wwwroot\passwordProtectCSharp\adminUser File.aspx.cs(422):
> > 'System.Web.UI.WebControls.Image' does not contain a definition for
> > 'Image'
> >
> > 3. For imgBox.Invalidate(),
> > C:\Inetpub\wwwroot\passwordProtectCSharp\adminUser File.aspx.cs(423):
> > 'System.Web.UI.WebControls.Image' does not contain a definition for
> > 'Invalidate'
> >
> > The related codes are attached below. Any suggestion? Thanks. -Dale
> >
> > VB:
> > Private Sub UseReaderBtn_Click(ByVal sender As System.Object, _
> > ByVal e As System.EventArgs) Handles UseReaderBtn.Click
> >
> > ' Construct a SQL string and a connection object
> > Dim sql As String = "SELECT UserPhoto FROM Users"
> > Dim conn As OleDbConnection = New OleDbConnection()
> > conn.ConnectionString = connectionString
> > ' Open connection
> > If conn.State <> ConnectionState.Open Then
> > conn.Open()
> > End If
> >
> > Dim cmd As OleDbCommand = New OleDbCommand(sql, conn)
> > Dim fs As FileStream
> > Dim bw As BinaryWriter
> > Dim bufferSize As Integer = 300000
> > Dim outbyte(300000 - 1) As Byte
> > Dim retval As Long
> > Dim startIndex As Long = 0
> > Dim pub_id As String = ""
> > Dim reader As OleDbDataReader = _
> > cmd.ExecuteReader(CommandBehavior.SequentialAccess )
> > ' Read first record
> > reader.Read()
> > fs = New FileStream(savedImageName, _
> > FileMode.OpenOrCreate, FileAccess.Write)
> > bw = New BinaryWriter(fs)
> > startIndex = 0
> > retval = reader.GetBytes(0, 0, outbyte, 0, bufferSize)
> > bw.Write(outbyte)
> > bw.Flush()
> > ' Close the output file.
> > bw.Close()
> > fs.Close()
> > reader.Close()
> > ' Display image
> > curImage = Image.FromFile(savedImageName)
> > PictureBox1.Image = curImage
> > PictureBox1.Invalidate()
> > ' Clean up connection
> > If conn.State = ConnectionState.Open Then
> > conn.Close()
> > ' Dispose connection
> > conn.Dispose()
> > End If
> > End Sub
> >
> > C#:
> > private void btnReadFmDB_Click(object sender, System.EventArgs e)
> > {
> > OleDbConnection dbConn;
> > OleDbCommand dbCmd;
> > OleDbDataReader dbDR;
> > string applicationState = ((string)(Application["DBType"])).ToLower();
> > string sConn = dbClass.Connect(applicationState);
> > // Construct a SQL string and a connection object
> > string sql = ("SELECT * FROM UserFiles WHERE Username =\'" +
> > (dbClass.DelimString(dListUsers.SelectedValue) + "\'"));
> > FileStream fs;
> > BinaryWriter bw;
> > int bufferSize = 300000;
> > byte[] outbyte;
> > long retval;
> > long startIndex = 0;
> > string pub_id = "";
> >
> > try
> > {
> > dbConn = new OleDbConnection(sConn);
> > dbConn.Open();
> > dbCmd = new OleDbCommand(sql, dbConn);
> > dbDR = dbCmd.ExecuteReader(CommandBehavior.CloseConnectio n);
> > while (dbDR.Read())
> > {
> > fs = new FileStream(savedImageName, FileMode.OpenOrCreate,
> > FileAccess.Write);
> > bw = new BinaryWriter(fs);
> > startIndex = 0;
> > retval = dbDR.GetBytes(0, 0, outbyte, 0, bufferSize);
> > bw.Write(outbyte);
> > bw.Flush();
> > // Close the output file.
> > bw.Close();
> > fs.Close();
> > }
> > // get the end
> > dbConn.Close();
> > }
> > catch (Exception excep)
> > {
> > Debug.WriteLine(excep.Message);
> > return;
> > }
> > // Display image
> > curImage = Image.FromFile(savedImageName);
> > imgBox.Image = curImage;
> > imgBox.Invalidate();
> > }[/color]
>
>
>[/color]
