This is the final part of this project. In this part
I will show you how to retrieve the saved image from database and view it in
the picturebox. At the end we will also focus on, how to delete the image from
database.
We have a listBox that populates all saved image’s
name. And you know imageName is the primary key of our SavedImages table. So it
is unique. We will gather image data querying by imagename. Listbox refreshes
the image list at page load event and save button click event. One more time it
will be refreshed when we will delete any image.
In bthShow_Click event we will use sqlDataReader. Our code for
btnShow_click event
private void bthShow_Click(object sender, EventArgs e)
{
SqlConnection Conn = new SqlConnection(GenerateString());
if (Conn.State == ConnectionState.Closed)
{
Conn.Open();
}
SqlCommand cmd = new SqlCommand();
cmd.Connection = Conn;
try
{
SqlDataReader reader;
cmd.CommandText = "SELECT
ImageData FROM SavedImages
where ImageName='" + listImageName.Text + "'";
reader = cmd.ExecuteReader();
while (reader.Read())
{
GetImage(pictureBox1, (byte[])reader["ImageData"]);
}
reader.Close();
}
catch (Exception ex)
{
MessageBox.Show(ex.Message);
}
}
Don’t be confused with GetImage(). It is a
function. I would like to remind you that we have saved image to database using
bytes arrey. Now to retrieve the image we have to convert the bytes into image.
Then we will be able to show it in picturebox. To convert byte arrey into image
data and view it in picturebox I have
used GetImage()
function.
public static void GetImage(PictureBox PictureImage, Byte[] ImageValue)
{
try
{
byte[] imageData = (byte[])ImageValue;
//Initialize
image variable
Image newImage;
//Read
image data into a memory stream
using (MemoryStream ms = new MemoryStream(imageData, 0, imageData.Length))
{
ms.Write(imageData, 0,
imageData.Length);
//Set image variable value using memory stream.
newImage = Image.FromStream(ms, true);
}
//set
picture
PictureImage.Image = newImage;
//return
PictureImage;
}
catch (Exception ex)
{
MessageBox.Show(ex.ToString());
}
}
Now just select any imagename and click on
Show button. That’s it.
If you want to show image by selectedIndexChange
event of the listBox, just use the code. Just call the
bthShow_Click event. It will work like a function.
private void listImageName_SelectedIndexChanged(object sender, EventArgs e)
{
bthShow_Click(sender, e);
}
Image delete :
Select an image name from the listbox and click on
the deletebutton. The code for image deletion is simple.
private void btnDelete_Click(object sender, EventArgs e)
{
if (MessageBox.Show("Do you want
to delete this image?", "Confirmation", MessageBoxButtons.YesNo, MessageBoxIcon.Question)
== System.Windows.Forms.DialogResult.No) return;
try
{
SqlCommandExecute("DELETE FROM SavedImages WHERE ImageName ='" + listImageName.Text + "'");
MessageBox.Show("Image deleted successfully.","Deleted");
frmImageSave_Load(sender,
e);
}
catch(Exception ex)
{
MessageBox.Show(ex.Message);
}
}
Here is the whole project in PDF format.
