I am trying to insert an image into Postgres and retrieve that image from postgresql using C#.
I have two columns in my table: memberid (character varying) and member_photo (bytea)
Here is my code to insert the image:
using (FileStream pgFileStream = new FileStream("D:\\Capture.jpg", FileMode.Open, FileAccess.Read))
{
using (BinaryReader pgReader = new BinaryReader(new BufferedStream(pgFileStream)))
{
NpgsqlCommand command = new NpgsqlCommand();
byte[] ImgByteA = pgReader.ReadBytes(Convert.ToInt32(pgFileStream.Length));
command.CommandText = "insert into membermaster (memberid, member_photo) VALUES ('65', #Image)";
command.Connection = Program.conn;
Program.conn.Close();
Program.conn.Open();
//command.Parameters.Add(new NpgsqlParameter("Image", ImgByteA));
command.Parameters.Add("#Image", ImgByteA).Value = ImgByteA;
command.ExecuteNonQuery();
Program.conn.Close();
}
}
Here is my code to retrieve the image
NpgsqlCommand command = new NpgsqlCommand();
command.CommandText = "select member_photo from membermaster where memberid='65'";
command.Connection = Program.conn;
try
{
Program.conn.Close();
Program.conn.Open();
byte[] productImageByte = command.ExecuteScalar() as byte[];
if (productImageByte != null)
{
using (MemoryStream productImageStream = new System.IO.MemoryStream(productImageByte))
{
ImageConverter imageConverter = new System.Drawing.ImageConverter();
pictureBox1.Image = imageConverter.ConvertFrom(productImageByte) as System.Drawing.Image;
// image.Save(imageFullPath, System.Drawing.Imaging.ImageFormat.Jpeg);
pictureBox1.Image = System.Drawing.Image.FromStream(productImageStream);
}
}
}
catch
{
Program.conn.Close();
throw;
}
The code to insert the image is working fine, but I can't show this image in a picturebox.
I get an error :
Parameter is not valid
Please help me solve this problem
AFAIK you cannot retrieve a byte[] using ExecuteScalar. You should use ExecuteReader instead. Just to be on the safe side when inserting parameters, I prefer to specify types myself, so my insert looks like this:
using (var conn = new NpgsqlConnection(connString))
{
string sQL = "insert into picturetable (id, photo) VALUES(65, #Image)";
using (var command = new NpgsqlCommand(sQL, conn))
{
NpgsqlParameter param = command.CreateParameter();
param.ParameterName = "#Image";
param.NpgsqlDbType = NpgsqlTypes.NpgsqlDbType.Bytea;
param.Value = ImgByteA;
command.Parameters.Add(param);
conn.Open();
command.ExecuteNonQuery();
}
}
I can then retrieve and load the image like this:
using (var conn = new NpgsqlConnection(connString))
{
string sQL = "SELECT photo from picturetable WHERE id = 65";
using (var command = new NpgsqlCommand(sQL, conn))
{
byte[] productImageByte = null;
conn.Open();
var rdr = command.ExecuteReader();
if (rdr.Read())
{
productImageByte = (byte[])rdr[0];
}
rdr.Close();
if (productImageByte != null)
{
using (MemoryStream productImageStream = new System.IO.MemoryStream(productImageByte))
{
ImageConverter imageConverter = new System.Drawing.ImageConverter();
pictureBox1.Image = imageConverter.ConvertFrom(productImageByte) as System.Drawing.Image;
}
}
}
}
I do not know if specifying the datatype on insert makes any difference, so try just retrieving using a Reader first. If that doesn't work, then I suggest changing your insert routine to something like mine.
Please note in my example id is an integer, not a character varying!
While the code in the accepted answer is working, it is not true that you cannot use ExecuteScalar. It might have been an issue in older versions, but using Npgsql 6.0.7 the following works:
public static async Task<byte[]?> GetByteaAsync(int id, string connectionString) {
byte[]? result = null;
await using (var con = new NpgsqlConnection(connectionString)) {
await con.OpenAsync();
await using (var cmd = new NpgsqlCommand("SELECT field_name from table_name where id=#id", con) {CommandType = CommandType.Text}) {
cmd.Parameters.Add("#id", NpgsqlDbType.Integer).Value = id;
result = ((byte[]?) await cmd.ExecuteScalarAsync());
}
await con.CloseAsync();
}
return result;
}
Related
This question already has answers here:
Retrieve Images from sql server database
(4 answers)
Closed 6 years ago.
I have a name & picutre saved in a database with this method:
Image img = Image.FromFile(imgLoc);
MemoryStream tmpStream = new MemoryStream();
img.Save(tmpStream, System.Drawing.Imaging.ImageFormat.Png);
tmpStream.Seek(0, SeekOrigin.Begin);
byte[] imgBytes = new byte[4000];
tmpStream.Read(imgBytes, 0, 4000);
string sqlquery = ("INSERT INTO Firma (Name, Logo)" +
"Values(#name, #logo)");
SqlCeCommand cmd = new SqlCeCommand(sqlquery, cn);
cmd.Parameters.AddWithValue("#name", tbName.Text);
cmd.Parameters.AddWithValue("#logo", imgBytes);
cmd.ExecuteNonQuery();
MessageBox.Show("Erfolgreich hinzugefügt!");
cn.Close();
this.Close();
Now I want to have the picture back and displayed in a picturebox.
My code does not work.
cn.Open();
comm = "SELECT Logo From Firma WHERE FirmenNr LIKE #Firma ";
cmd = new SqlCeCommand(comm, cn);
cmd.Parameters.Add("#Firma", SqlDbType.NVarChar, 100).Value = FirmenNr.ToString();
SqlCeDataAdapter dataAdapter = new SqlCeDataAdapter(cmd);
DataSet dataSet = new DataSet();
dataAdapter.Fill(dataSet);
if (dataSet.Tables[0].Rows.Count == 1)
{
Byte[] data = new Byte[0];
data = (Byte[])(dataSet.Tables[0].Rows[0]["pic"]);
MemoryStream mem = new MemoryStream(data);
pictureBox1.Image = Image.FromStream(mem);
}
cn.Close();
the picture is safed as binary with the length 4000.
EDIT: how can I make this larger? visual studio does not allow me to set it to values above 4030.
You have a mistake here:
data = (Byte[])(dataSet.Tables[0].Rows[0]["pic"]);
You're accessing the column pic, but you query for Logo
Method to Put File into database from Drive:
public static void databaseFilePut(string imgLoc) {
byte[] file;
using (var stream = new FileStream(imgLoc, FileMode.Open, FileAccess.Read)) {
using (var reader = new BinaryReader(stream)) {
file = reader.ReadBytes((int) stream.Length);
}
}
using (var varConnection = Locale.sqlConnectOneTime(Locale.sqlDataConnectionDetails))
using (var sqlWrite = new SqlCommand("INSERT INTO Firma(Name, Logo)Values(#File)", varConnection)) {
sqlWrite.Parameters.Add("#File", SqlDbType.VarBinary, file.Length).Value = file;
sqlWrite.ExecuteNonQuery();
}
}
This method is to Get File from Database and Show In Picture Tool:
public static void databaseFileRead(string varID, string varPathToNewLocation) {
MemoryStream memoryStream = new MemoryStream();
using (var varConnection = Locale.sqlConnectOneTime(Locale.sqlDataConnectionDetails))
using (var sqlQuery = new SqlCommand(#"SELECT [Logo] FROM [dbo].[Firma] WHERE [RaportID] = #varID", varConnection)) {
sqlQuery.Parameters.AddWithValue("#varID", varID);
using (var sqlQueryResult = sqlQuery.ExecuteReader())
if (sqlQueryResult != null) {
sqlQueryResult.Read();
var blob = new Byte[(sqlQueryResult.GetBytes(0, 0, null, 0, int.MaxValue))];
sqlQueryResult.GetBytes(0, 0, blob, 0, blob.Length);
//using (var fs = new MemoryStream(memoryStream, FileMode.Create, FileAccess.Write)) {
memoryStream.Write(blob, 0, blob.Length);
//}
}
}
pictureBox1.Image = Image.FromStream(memoryStream);
}
I am trying to get a little tool to work, for our little company.
This should fill data from a DataGridView into a SQL Server Standard database.
Reading out the SQL table is working fine, but I can't get the tool to write the values.
I get the error mentioned in the title.
Here the code:
var kdNummer = new SqlParameter("Kundennummer", SqlDbType.Int);
var kdName = new SqlParameter("Kundenname", SqlDbType.VarChar);
var kdMail = new SqlParameter("Kundenmail", SqlDbType.VarChar);
var kdTele = new SqlParameter("Telefon", SqlDbType.VarChar);
string kdquery = "INSERT INTO Kunden VALUES (#Kundennummer, #Kundenname, #Kundenmail, #Telefon)";
using (SqlConnection updatedb = new SqlConnection("Data Source=;Initial Catalog=updatedb;User ID=;Password="))
{
updatedb.Open();
for (int i = 0;i<dataGridView1.Rows.Count;i++)
{
using(SqlCommand NrDaten = new SqlCommand(kdquery, updatedb))
{
kdNummer.Value = dataGridView1.Rows[i].Cells["Kundennummer"].Value;
NrDaten.Parameters.Add(kdNummer);
NrDaten.ExecuteNonQuery();
}
using (SqlCommand NameDaten = new SqlCommand(kdquery, updatedb))
{
kdName.Value = dataGridView1.Rows[i].Cells["Kundenname"].Value;
NameDaten.Parameters.Add(kdName);
NameDaten.ExecuteNonQuery();
}
using (SqlCommand MailDaten = new SqlCommand(kdquery, updatedb))
{
kdMail.Value = dataGridView1.Rows[i].Cells["Kundenmail"].Value;
MailDaten.Parameters.Add(kdMail);
MailDaten.ExecuteNonQuery();
}
using (SqlCommand TeleDaten = new SqlCommand(kdquery, updatedb))
{
kdTele.Value = dataGridView1.Rows[i].Cells["Telefon"].Value;
TeleDaten.Parameters.Add(kdTele);
TeleDaten.ExecuteNonQuery();
}
}
updatedb.Close();
}
Your query requires 4 parameters, but you're always only setting one (also please note that in the SqlParameter you need to have the # sign as well). Thus you get an error about missing parameters. Your code should probably look like this:
var kdNummer = new SqlParameter("#Kundennummer", SqlDbType.Int);
var kdName = new SqlParameter("#Kundenname", SqlDbType.VarChar);
var kdMail = new SqlParameter("#Kundenmail", SqlDbType.VarChar);
var kdTele = new SqlParameter("#Telefon", SqlDbType.VarChar);
string kdquery = "INSERT INTO Kunden VALUES (#Kundennummer, #Kundenname, #Kundenmail, #Telefon)";
using (SqlConnection updatedb = new SqlConnection("..."))
{
updatedb.Open();
using (SqlCommand insert = new SqlCommand(kdquery, updatedb))
{
insert.Parameters.Add(kdName);
insert.Parameters.Add(kdNummer);
insert.Parameters.Add(kdMail);
insert.Parameters.Add(kdTele);
for (int i = 0;i<dataGridView1.Rows.Count;i++)
{
kdName.Value = dataGridView1.Rows[i].Cells["Kundenname"].Value;
kdNummer.Value = dataGridView1.Rows[i].Cells["Kundennummer"].Value;
kdMail.Value = dataGridView1.Rows[i].Cells["Kundenmail"].Value;
kdTele.Value = dataGridView1.Rows[i].Cells["Telefon"].Value;
insert.ExecuteNonQuery();
}
}
}
Or even shorter:
string kdquery = "INSERT INTO Kunden VALUES (#Kundennummer, #Kundenname, #Kundenmail, #Telefon)";
using (SqlConnection updatedb = new SqlConnection("..."))
{
updatedb.Open();
for (int i = 0;i<dataGridView1.Rows.Count;i++)
{
using (SqlCommand insert = new SqlCommand(kdquery, updatedb))
{
insert.Parameters.AddWithValue("#Kundenname", dataGridView1.Rows[i].Cells["Kundenname"].Value);
insert.Parameters.AddWithValue("#Kundennummer", dataGridView1.Rows[i].Cells["Kundennummer"].Value);
insert.Parameters.AddWithValue("#Kundenmail", dataGridView1.Rows[i].Cells["Kundenmail"].Value);
insert.Parameters.AddWithValue("#Telefon", dataGridView1.Rows[i].Cells["Telefon"].Value);
insert.ExecuteNonQuery();
}
}
}
EDIT: I modified the long version of the code for maximum re-use of instances. Otherwise you get the errors mentioned in your comment.
I want to retrieve an image from an Oracle database to an Image control in asp.net. I tried but it's not working.
This is the code used for inserting image into database:
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();
}
Table:
Id Name Photo
1 C:\\user\pictures\animal.jpeg (BLOB)
Below is the code used to retrieve the image into an image control but this code is not working.
For the past two days I've been struggling with this
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)
{
}
}
Any ideas? Thanks in advance
maybe this code can help you:
public Image byteArrayToImage(byte[] byteArrayIn)
{
MemoryStream ms = new MemoryStream(byteArrayIn);
Image returnImage = Image.FromStream(ms);
return returnImage;
}
i'm trying to load images from database to a PictureBox. I use these following codes in order to load them to my picture. I've written some code but don't know what I should do for continuing.
Any help will be appreciated.
private void button1_Click(object sender, EventArgs e)
{
sql = new SqlConnection(#"Data Source=PC-PC\PC;Initial Catalog=Test;Integrated Security=True");
cmd = new SqlCommand();
cmd.Connection = sql;
cmd.CommandText = ("select Image from Entry where EntryID =#EntryID");
cmd.Parameters.AddWithValue("#EntryID", Convert.ToInt32(textBox1.Text));
}
Continue with something like this in the button1_Click:
// Your code first, here.
var da = new SqlDataAdapter(cmd);
var ds = new DataSet();
da.Fill(ds, "Images");
int count = ds.Tables["Images"].Rows.Count;
if (count > 0)
{
var data = (Byte[])ds.Tables["Images"].Rows[count - 1]["Image"];
var stream = new MemoryStream(data);
pictureBox1.Image = Image.FromStream(stream);
}
Assuming we have a simple database with a table called BLOBTest:
CREATE TABLE BLOBTest
(
BLOBID INT IDENTITY NOT NULL,
BLOBData IMAGE NOT NULL
)
We could retrieve the image to code in the following way:
try
{
SqlConnection cn = new SqlConnection(strCn);
cn.Open();
//Retrieve BLOB from database into DataSet.
SqlCommand cmd = new SqlCommand("SELECT BLOBID, BLOBData FROM BLOBTest ORDER BY BLOBID", cn);
SqlDataAdapter da = new SqlDataAdapter(cmd);
DataSet ds = new DataSet();
da.Fill(ds, "BLOBTest");
int c = ds.Tables["BLOBTest"].Rows.Count;
if(c>0)
{ //BLOB is read into Byte array, then used to construct MemoryStream,
//then passed to PictureBox.
Byte[] byteBLOBData = new Byte[0];
byteBLOBData = (Byte[])(ds.Tables["BLOBTest"].Rows[c - 1]["BLOBData"]);
MemoryStream stmBLOBData = new MemoryStream(byteBLOBData);
pictureBox1.Image= Image.FromStream(stmBLOBData);
}
cn.Close();
}
catch(Exception ex)
{MessageBox.Show(ex.Message);}
This code retrieves the rows from the BLOBTest table in the database into a DataSet, copies the most recently added image into a Byte array and then into a MemoryStream object, and then loads the MemoryStream into the Image property of the PictureBox control.
Full reference guide:
http://support.microsoft.com/kb/317701
private void btnShowImage_Click(object sender, EventArgs e)
{
string constr = "Provider=Microsoft.Jet.OLEDB.4.0;Data Source=.\\PIS(ACU).mdb;";
Con = new OleDbConnection(#constr);
Con.Open();
Com = new OleDbCommand();
Com.Connection = Con;
Com.CommandText = "SELECT Photo FROM PatientImages WHERE Patient_Id = " + val + " ";
OleDbDataReader reader = Com.ExecuteReader();
if (reader.Read())
{
byte[] picbyte = reader["Photo"] as byte[] ?? null;
if (picbyte != null)
{
MemoryStream mstream = new MemoryStream(picbyte);
pictureBoxForImage.Image = System.Drawing.Image.FromStream(mstream);
{
System.Drawing.Bitmap bmp = new System.Drawing.Bitmap(mstream);
}
}
HERE IS A TOTAL ANOTHER WAY TO DO SO:
You can simply convert the Image to Text before saving it into DataBase and the then convert it back to the Image after reading it:
public string ImageToStringFucntion(Image img)
{
try
{
using (MemoryStream ms = new MemoryStream())
{
img.Save(ms, System.Drawing.Imaging.ImageFormat.Png);
byte[] imgBytes = ms.ToArray();
string FinalText = Convert.ToBase64String(imgBytes, 0 , imgBytes.Length);
return FinalText;
}
}
catch
{
return null;
}
}
Now you can Insert or Update your Database...
Now Let's consider you want it back:
public Image StringToImage_(string input_)
{
try
{
byte[] imgBytes = Convert.FromBase64String(input_);
using (MemoryStream ms = new MemoryStream(imgBytes))
{
Image img = Image.FromStream(ms, true);
return img;
}
}
catch (Exception ex)
{
return null;
}
}
Now you can do as follow:
// Considering you have already pulled your data
// from database and set it in a DataSet called 'ds',
// and you picture is on the field number [1] of your DataRow
pictureBox1.Image = StringToImage_(ds.Table[0].Rows[0][1].ToString());
I'm trying to convert images to insert into Microsoft Access Database in C#.Net Windows Form.
And also i want to delete and alter image.
But I don't know how to do that.
Please write a code segment for me.
I'd convert the image to a byte[] and. Then convert the byte[] back to an image.
public static byte[] ImageToByte(Image img)
{
ImageConverter converter = new ImageConverter();
return (byte[])converter.ConvertTo(img, typeof(byte[]));
}
public static Image ImageFromByte(byte[] image)
{
ImageConverter ic = new ImageConverter();
Image img = (Image)ic.ConvertFrom(image);
return img;
}
The following link will help you:
http://social.msdn.microsoft.com/forums/en-US/winformsdatacontrols/thread/c3fae255-9d2e-45e9-b830-58d544fc43ee/
Conversion will be in the following lines of the above link:
using ( FileStream fs = fi.OpenRead() )
{
bData = new byte[fi.Length];
int nReadLength = fs.Read( bData,0, (int)(fi.Length) );
}
Hope this helps...
using (var connection = new OleDbConnection(#"Provider=Microsoft.ACE.OLEDB.12.0;Data Source=C:\BlankDatabase.mdb"))
{
connection.Open();
// Create table
using (var command = connection.CreateCommand())
{
command.CommandText = #"
CREATE TABLE FileTable (
FileName VARCHAR(255),
File IMAGE)
";
command.ExecuteNonQuery();
}
var imageContent = File.ReadAllBytes(#"C:\logo.png");
// upload image to the table
using (var command = connection.CreateCommand())
{
command.CommandText = #"
INSERT INTO FileTable (FileName, File)
VALUES (#FileName, #File)
";
command.Parameters.AddWithValue("#FileName", "Logo");
command.Parameters.AddWithValue("#File", imageContent);
command.ExecuteNonQuery();
}
// retreive image from the table
using (var command = connection.CreateCommand())
{
command.CommandText = #"
SELECT File
FROM FileTable
WHERE FileName = 'Logo'
";
var readImageContent = (byte[])command.ExecuteScalar();
File.WriteAllBytes(#"C:\logo1.png", readImageContent);
}
// alter image from the table
using (var command = connection.CreateCommand())
{
command.CommandText = #"
UPDATE FileTable
SET File = #File
WHERE FileName = 'Logo'
";
command.Parameters.AddWithValue("#File", imageContent);
command.ExecuteNonQuery();
}
// delete image from the table
using (var command = connection.CreateCommand())
{
command.CommandText = #"
DELETE FROM FileTable
WHERE FileName = 'Logo'
";
command.ExecuteNonQuery();
}
}
In this code BlankDatabase.mdb is an empty MS Access database file.