I would like to know why my data is not saving permanently in my local database. If I close my application and open it again. I cannot download the uploaded data. Its showing an error called "The given key was not present in the dictionary” But I can download the file when the application is running. I mean, if the application is running and I upload a data to my grid, then i can download it without any error. If the application is closed and opened, that time if I try to download the same old file its throwing the error
My code
private void DownloadAttachment(DataGridViewCell dgvCell)
{
string fileName = Convert.ToString(dgvCell.Value);
//Return if the cell is empty
if (fileName == string.Empty)
return;
FileInfo fileInfo = new FileInfo(fileName);
string fileExtension = fileInfo.Extension;
byte[] byteData = null;
//show save as dialog
using (SaveFileDialog saveFileDialog1 = new SaveFileDialog())
{
//Set Save dialog properties
saveFileDialog1.Filter = "Files (*" + fileExtension + ")|*" + fileExtension;
saveFileDialog1.Title = "Save File as";
saveFileDialog1.CheckPathExists = true;
saveFileDialog1.FileName = fileName;
if (saveFileDialog1.ShowDialog() == DialogResult.OK)
{
cncInfoDataGridView.Rows[dgvCell.RowIndex].Cells[1].Value = fileInfo.Name;
byteData = _myAttachments[dgvCell.RowIndex];
File.WriteAllBytes(saveFileDialog1.FileName, byteData);
}
}
}
Also if anybody could tell me a sample program to upload and download a file or document to/from the database.mdf and to view in
grid view with out using the sql server. because i dont want to use the sql server. Just using a local database.
Please anybody help me to find the right code.
Thanks in advance.